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Understanding the galvanic corrosion of the Q-phase/Al couple using SVET and SIET

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Journal of Materials Science & Technology 2019年第7期35卷 1444-1454页

作者： Alexander I.Ikeuba Bo Zhang Jianqiu Wang En-Hou Han Wei Ke Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences (UCAS) 19A Yuquan RoadShijingshan DistrictBeijing100049China Department of Pure and Applied Chemistry University of CalabarCalabarPMB 1115 Nigeria

The galvanic corrosion of the Q-phase/Al couple in 0.1 M NaCl solutions has been studied using the scanning vibrating electrode technique (SVET)f the scanning ion-selective electrode technique (SIET) and energy dispersive X-ray spectroscopy (EDX). The galvanic corrosion of the Q-phase/Al couple was found to be dependent on pH and immersion time. Current density maps obtained by SVET shows that the anodic oxidation processes emerge from Al in a localized manner in pH 2 and 6 solutions but is initiated in a uniform manner in pH 13 solution, whereas, the cathodic processes are more homogeneously distributed over the Q-phase at pH 2.6 and 13. It is seen that the Q-phase remains cathodic in the Q-phase/Al couple in acidic, neutral and alkaline solutions indicating that the galvanic polarity of the Q-phase is independent of pH. The effect of the galvanic corrosion was largest at pH 2 and 13 compared to pH 6. The pH map obtained by SIET indicates that the galvanic activity of the Q-phase/Al couple proceeds via heavy alkalization of the Q-phase surface with the generation of appreciable amounts of OH~ ions. The enrichment of Cu indicated by EDX is responsible for the observed cathodic activity of the Q-phase in the Q-phase/Al couple.

关键词： Q-phase Galvanic corrosion Scanning vibrating electrode technique (SVET) Scanning ion-selective electrode technique (SIET) Energy dispersive X-ray spectroscopy (EDX)

Non-invasive Healthcare Analytical Platform Based on Organic Electrochemical Transistors

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Chemical Research in Chinese Universities 2024年第5期40卷 824-848页

作者： HU Xingyu MAO Ning YAN Xinwen HUANG Ling LIU Xu YANG Huige SUN Qingqing LIU Xuying JIA Hanyu School of Materials&Engineering Zhengzhou UniversityZhengzhou450001P.R.China Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education&Hubei Key Laboratory of Catalysis and Materials Science Hubei R&D Center of Hyperbranched Polymers Synthesis and ApplicationsSouth-Central University for NationalitiesWuhan430074P.R.China Science&Technology Innovation Center for Advanced Materials of Intelligent Equipment Longmen LaboratoryLuoyang471000P.R.China

Non-invasive bioelectronics,especially organic electrochemical transistors(OECTs),have drawn extensive attentions of academical and medical communities by virtue of their efficient bio-electronic interfacing,water-involved ionic transport,excellent ionic-electronic coupling,ultralow power consumption,wide detectable range,and outstanding detection *** structure diversity,low-temperature solution processability,facile bio/chemical functionalization,and excellent biocompatibility of organic mixed ionic-electronic conductors(OMIECs)render OECTs particularly suitable for non-invasive or minimally invasive healthcare analytical ***,we comprehensively review recent advances of the non-invasive analytical healthcare applications based on OECTs,especially on the detection of biomarkers or metabolites in the excretory biofluids,as well as the recording of electrophysiological signals.A brief introduction of OECT and its comparison with other organic thin-film transistors upon device configuration and working mechanism are firstly ***-of-the-art non-invasive OECT-based biosensors are summarized on their detection of ionic and molecular biomarkers,following with circuit design strategies of OECTs for real-time and in-situ electrophysiological recording from skin *** conclusion,remaining barriers and future challenges of non-invasive OECT-based bioelectronics towards lower detection limit,more accurate quantitative relationship between analyte concentrations and measured parameters,more intimate device-tissue interface,and long-term operation stability are deeply analyzed with a critical outlook.

关键词： Organic electrochemical transistor Non-invasive Bioelectronics ion-selective Electrophysiological monitoring

Solid-Contact Perchlorate Sensor with Nanomolar Detection Limit Based on Cobalt Phthalocyanine ionophores Covalently Attached to Polyacrylamide

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American Journal of Analytical Chemistry 2011年第7期2卷 820-831页

作者： Mohammad Nooredeen Abbas Abdel Lattief A. Radwan Philippe Bühlmann Mahmud A. Abd El Ghaffar 不详

Novel solid-contact perchlorate sensors based on cobalt phthalocyanine-C-monocarboxylic acid (I), and cobalt phthalocyanine-C,C,C,C-tetracarboxylic acid (II) as free ionophores and covalently attached to polyacryla- mide (PAA)—ionophores III and IV, respectively were prepared. The all solid-state sensors were constructed by the application of a thin film of a polymer cocktail containing a phthalocyanine ionophore and cetyltrimethylammonium bromide (CTMAB) as a lipophilic cationic additive onto a gold electrode precoated with the conducting polymer poly (3,4-ethylenedioxythiophene) (PEDOT) as an ion and electron transducer. The sensor with 10.3% of ionophore (III) covalently attached to plasticizer-free poly (butyl methacrylate-co-do- decyl methacrylate) (PBDA) exhibited a good selectivity for perchlorate and discriminated many ions, in- cluding F–, Cl–, Br–, I–, SCN–, , S2– and . The covalent attachment of the ionophore to the polymer resulted in a near-Nernstian anionic slope of –62.3 mV/decade whereas a super-Nernstian slope of –79.9 mV/ decade was obtained for the free ionophore. The sensor covered a linear concentration range of 5 × 10–9 - 1 × 10–2 mol?L–1 with a lower detection limit (LDL) of 1 × 10–9 mol?L–1 and gave a stable response over a pH range of 4 - 10.5. The all-solid state sensors were utilized for the selective flow injection potentiometric determination of perchlorate in natural water and human urine samples in the nanomolar concentration range.

关键词： ion-selective Electrode Solid Contact Covalent ionophore Attachment Perchlorate Flow-Injection Analysis Urine

A New Potentiometric Sensor for Determination of Pethidine hydrochloride in Ampoules and Urine

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American Journal of Analytical Chemistry 2011年第1期2卷 56-65页

作者： Hazem M. Abu-Shawish Nasser Abu Ghalwa Ghada I. Khraish Jehad Hammad 不详

A simple, precise, rapid and low-cost potentiometric method for pethidine determination in pharmaceuticals and urine is proposed. A chemically modified carbon paste electrode (CMCPE) for pethidine hydrochloride (PDCl) based on pethidine-phosphotungstate (PD-PT) as ion-pair complex was prepared and fully character-ized in terms of composition, usable pH range, response time and temperature. The pethidine electrode showed Nernstain responses in the concentration range 2.1 × 10–6-1.0 × 10–2 M with a detection limit of 7.3 × 10-7 and usable within the pH range 3.5-6.6. This sensor exhibited a fast response time (about 5-8 s), good stability. The value (dE/dt) of the electrode was found to be 0.00071 V/?C, which indicates fairly high ther-mal stability. Selectivity coefficients determined by matched potential method (MPM) and separate solution method (SSM) showed high selectivity for PDCl with respect to a large number of inorganic cations, organic cations, sugars and some common drug excipients. The sensor could be used successfully in the estimation of PDCl in ampoules and in spiked urine samples.

关键词： Potentiometry Carbon Paste Electrode Pethidine ion-selective Electrode

STUDIES ON RESPONSE CHARACTERISTICS OF DRUG ISE'S (Ⅳ) SELECTIVITY OF, DRUG ISE'S WITH HETERO-POLY ACID ANion SITE TOWARD METAL ionS

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Science China Chemistry 1990年第5期33卷 562-571页

作者：姚守拙马万里聂利华 New Material Research Institute Hunan University Changsha 410012 PRC

The relationship between the selectivity of six drug ion-selective electrodes with anionic species of hetero-poly acid as exchange site and the structural and thermodynamical parameters of the metal ion has been investigated experimentally and theoretically. The electrode selectivity is controlled mainly by the extractibility or hydrophobicity of the metal ion, but not by the ion-association-complex formation process. Linear relationship exists between the pK_(ij) value and the structural parameter z^2/(r + 0.85) and the thermodynamic parameter of hydration (△G_h) of the metal ion. Better correlation is obtained for the pK_(ij)vs. (z^2/r)^(-k) relationship.

关键词： ion-selective electrode electrode selectivity hetero-poly acid anion site metal ion.

STUDIES ON RESPONSE CHARACTERISTICS OF DRUG ISE'S (Ⅶ)——PERFORMANCE AND THEORETICAL TREATMENT OF MICROCELLS CONNECTED IN SERIES

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Science China Chemistry 1990年第6期33卷 694-703页

作者：姚守拙马万里聂利华 New Material Research Institute Hunan University Changsha 410012 PRC

A new type of MCCS (microcells connected in series) has been constructed and its performances investigated. It has been applied to the determination of streptomycin. The sensitivity and accuracy have been increased significantly. A theoretical model for the error of determination using the MCCS has been suggested and proved experimentally using the Monte Carlo method, and the error model proposed in Ref. [1] revised.

关键词： ion-selective electrode streptomycin cells connected in series Monte Carlo method.