Microelectrode Arrays: A General Strategy for Using Oxidation Reactions To Site Selectively Modify Electrode Surfaces

Langmuir ◽  
2014 ◽  
Vol 30 (8) ◽  
pp. 2280-2286 ◽  
Author(s):  
Bichlien H. Nguyen ◽  
David Kesselring ◽  
Eden Tesfu ◽  
Kevin D. Moeller
Keyword(s):  
Microelectrode Arrays ◽  
General Strategy ◽  
Oxidation Reactions ◽  
Modify Electrode ◽  
Electrode Surfaces

The Lead Dioxide Anode. II. The Kinetics and Participation of the Lead Dioxide Electrode in Electrochemical Oxidation Reactions in Sulfuric Acid

1989 ◽  
Vol 42 (9) ◽  
pp. 1527 ◽  
Author(s):  
TH Randle ◽  
AT Kuhn
Keyword(s):  
Sulfuric Acid ◽  
Electrochemical Oxidation ◽  
Maximum Rate ◽  
Lead Dioxide ◽  
Chemical Oxidation ◽  
Oxidation Reactions ◽  
Electrochemical Regeneration ◽  
Electrode Surfaces ◽  
Lead Dioxide Electrode ◽  
Lead Dioxide Anode

Lead dioxide is a strong oxidizer in sulfuric acid, consequently electrochemical oxidation of solution species at a lead dioxide anode may occur by a two-step, C-E process (chemical oxidation of solution species by PbO2 followed by electrochemical regeneration of the reduced lead dioxide surface). The maximum rate of each step has been determined in sulfuric acid for specified lead dioxide surfaces and compared with the rates observed for the electrochemical oxidation of cerium(III) and manganese(II) on the same electrode surfaces. While the rate of electrochemical oxidation of a partially reduced PbO2 surface may be sufficient to support the observed rates of CeIII and MnII oxidation at the lead dioxide anode, the rate of chemical reaction between PbO2 and the reducing species is not. Hence it is concluded that the lead dioxide electrode functions as a simple, 'inert' electron-transfer agent during the electrochemical oxidation of CellI and MnII in sulfuric acid. In general, it will most probably be the rate of the chemical step which determines the feasibility or otherwise of the C-E mechanism.

scholarly journals Modification of Electrode Surfaces Via Chromium Deposition [Capital University]

2019 ◽  
Author(s):  
David Kenneth Lankitus ◽  
William J. Clark
Keyword(s):  
Microelectrode Array ◽  
Microelectrode Arrays ◽  
Differential Pulse ◽  
Glassy Carbon Electrodes ◽  
Electrode Surfaces ◽  
Undergraduate Laboratory ◽  
Covered Electrodes ◽  
Source Current ◽  
Reduction And Oxidation ◽  
Electrode Coverage

Microelectrode arrays are useful in electrochemical detection, having the advantage of lower signal to noise ratios compared to traditional sized electrodes. However, they can be expensive and complex to produce. A cheap, easy to produce, and renewable method of preparing microelectrode arrays in an undergraduate laboratory is therefore highly valuable. This project explores the efficacy of producing a random-microelectrode array by partial deposition of chromium onto an electrode surface, enhancing the study of electrochemistry in undergraduate laboratories. This study uses gold, platinum, and glassy carbon electrodes, ruthenium hexamine as a model electron acceptor, and K2Cr2O7 solution as a chromium source. Current results have produced evidence of microelectrode formation. All electrodes have been completely and partially inactivated by chromium deposition via reduction of Cr(VI) to Cr(III) and can be reactivated electrochemically as well. Deposition is achieved through direct current potential amperometry (DCPA) and illustrated through both cyclic voltammetry (CV) and differential pulse voltammetry (DPV). CVs reveal reduction and oxidation of ruthenium hexamine with uncovered electrodes and a loss of reduction and oxidation with chromium covered electrodes. DPVs reveal similar results. The partial deposition that has been achieved can be difficult to replicate and varies with the electrode material. Background CV scans differ in active and inactivated electrodes, suggesting that capacitance varies with deposition. By measuring capacitance compared to deposition, insight regarding electrode coverage may be found. Experiments aimed at replicating published material on microelectrode production (Anal. Chem. 2016, 88, 1753-1759) are also being performed to demonstrate similarities between results. Comparison to published work and refined methodology is needed to provide strong, reproducible evidence of random-microelectrode array production.

Towards Systematization

1977 ◽  
Vol 16 (03) ◽  
pp. 125-130 ◽  
Author(s):  
P. L. Reichertz
Keyword(s):  
Clinical Medicine ◽  
Medical Science ◽  
User Involvement ◽  
Empirical Science ◽  
Target System ◽  
General Strategy ◽  
System Construction ◽  
Formal Approach ◽  
Methodology Development ◽  
Planning Development

Data processing has become an important tool in theoretical and clinical medicine. The main categories of applications are : information analysis, (bio)signal processing and the field of information logistics (information systems).The problems encountered lie in the discrepancy of the basic methods of a formal approach to an empirical science, the complexity of the target system and the system ecology, i.e. the involvement of the user and the system environment during system construction and utilization.Possible solutions to these problems are the application of system techniques, inductive planning, development of medical methodology, development of methods and techniques for user involvement and assessment of motivation and education and educational planning.The necessary general strategy in the development in medical informatics is seen in the continuing systematization of the theoretical and practical approach. It is estimated that this will eventually contribute to the systematization of medical science and practice.

Mechanism of Oxidation Reactions of Bromine

1958 ◽  
Vol 14 (5_6) ◽  
pp. 357-360
Author(s):  
K. C. Grover ◽  
R. C. Mehrotra
Keyword(s):  
Oxidation Reactions ◽  
Mechanism Of Oxidation

Mechanism of Oxidation Reactions of Bromine

1958 ◽  
Vol 14 (5_6) ◽  
pp. 345-356 ◽  
Author(s):  
K. C. Grover ◽  
R. C. Mehrotra
Keyword(s):  
Oxidation Reactions ◽  
Mechanism Of Oxidation

The Plasma Technology for Shaping the Electric Pacemaker Electrode Surfaces Coated with Ruthenium

Vestnik MEI ◽  
2019 ◽  
Vol 6 ◽  
pp. 64-70
Author(s):  
Yuriy V. Martynenko ◽  
◽  
Vyacheslav P. Budaev ◽  
Keyword(s):  
Plasma Technology ◽  
Electrode Surfaces

Thermo-Oxidative Decomposition of Lovage (Levisticum officinale) and Davana (Artemisia pallens) Essential Oils under Simulated Tobacco Heating Product Conditions

2020 ◽  
Vol 29 (1) ◽  
pp. 27-43
Author(s):  
Emma Jakab ◽  
Zoltán Sebestyén ◽  
Bence Babinszki ◽  
Eszter Barta-Rajnai ◽  
Zsuzsanna Czégény ◽  
...  
Keyword(s):  
Low Temperature ◽  
Essential Oils ◽  
Relative Yield ◽  
Gas Chromatography Mass Spectrometry ◽  
Intramolecular Rearrangement ◽  
Oxidation Reactions ◽  
Pyrolysis Gas ◽  
Oxidative Decomposition ◽  
Oxidative Pyrolysis ◽  
Artemisia Pallens

SummaryThe thermo-oxidative decomposition of lovage (Levisticum officinale) and davana (Artemisia pallens) essential oils has been studied by pyrolysis-gas chromatography/mass spectrometry in 9% oxygen and 91% nitrogen atmosphere at 300 °C to simulate low-temperature tobacco heating conditions. Both lovage and davana oils contain numerous chemical substances; the main components of both oils are various oxygen-containing compounds. Isobenzofuranones are the most important constituents of lovage oil, and their relative intensity changed significantly during oxidative pyrolysis. (Z)-ligustilide underwent two kinds of decomposition reactions: an aromatization reaction resulting in the formation of butylidenephthalide and the scission of the lactone ring with the elimination of carbon dioxide or carbon monoxide. Davanone is the main component of davana oil, which did not decompose considerably during low-temperature oxidative pyrolysis. However, the relative yield of the second most intensive component, bicyclogermacrene, reduced markedly due to bond rearrangement reactions. Davana ether underwent oxidation reactions leading to the formation of various furanic compounds. The changes in the composition of both essential oils could be interpreted in terms of bond splitting, intramolecular rearrangement mechanisms and oxidation reactions of several constituents during low-temperature oxidative pyrolysis. The applied thermo-oxidative method was found to be suitable to study the stability of the essential oils and monitor the decomposition products under simulated tobacco heating conditions. In spite of the complicated composition of the essential oils, no evidence for interaction between the oil components was found. [Beitr. Tabakforsch. Int. 29 (2020) 27–43]

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