Effect of the molar concentration of pyrrole monomer on the rate of polymerization, growth and hence the electrochemical behavior of highly pristine PPy flexible electrodes

The PMo12-PPy heterogeneous cathode was synthesized electrochemically. In doing so, the PMo12 redox-active material was impregnated throughout the conductive polymer matrix of the poly(pyrrole) nanowires. All chemicals and reagents used were purchased from Sigma-Aldrich. Anodized aluminum oxide (AAO) purchased from Whatman served as the porous hard template for nanowire deposition. A thin layer of gold of approximately 200nm was sputtered onto the disordered side of the AAO membrane to serve as the current collector. Copper tape was connected to the sputtered gold for contact and the device was sealed in parafilm with heat with an exposed area of 0.32 cm2 to serve as the electroactive area for deposition. All electrochemical synthesis and experiments were conducted using a Bio-Logic MPG2 potentiostat. The deposition was carried out using a 3-electrode beaker cell setup with a solution of acetonitrile containing 5mM and 14mM of the phosphomolybdic acid and pyrrole monomer, respectively. The synthesis was achieved using chronoamperometry to apply a constant voltage of 0.8V vs. Ag/AgCl (BASi) to oxidatively polymerize the pyrrole monomer to poly(pyrrole). To prevent the POM from chemically polymerizing the pyrrole, an injection method was used in which the pyrrole monomer was added to the POM solution only after the deposition voltage had already been applied. The deposition was well controlled by limiting the amount of charge transferred to 300mC. Following deposition, the AAO template was removed by soaking in 3M sodium hydroxide (NaOH) for 20 minutes and rinsed several times with water. After synthesis, all cathodes underwent electrochemical testing to determine their performance using cyclic voltammetry and constant current charge-discharge cycling in 0.1 M Mg(ClO4)2/PC electrolyte. The cathodes were further characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), and x-ray photoelectron spectroscopy (XPS).

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SPECIFIC PROPERTIES OF TUBULIN IN THE PREFRONTAL CORTEX IN CONTROL, SCHIZOPHRENIA AND VASCULAR DEMENTIA

"Medical & pharmaceutical journal "Pulse" ◽

10.26787/nydha-2686-6838-2020-22-11-65-71 ◽

2020 ◽

pp. 65-71

Author(s):

Burbaeva G.Sh. ◽

Androsova L.V. ◽

Vorobyeva E.A. ◽

Savushkina O.K.

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Prefrontal Cortex ◽

Vascular Dementia ◽

Binding Activity ◽

Nephelometric Method ◽

Rate Of Polymerization ◽

Mental Diseases ◽

And Control ◽

The Brain

The aim of the study was to evaluate the rate of polymerization of tubulin into microtubules and determine the level of colchicine binding (colchicine-binding activity of tubulin) in the prefrontal cortex in schizophrenia, vascular dementia (VD) and control. Colchicine-binding activity of tubulin was determined by Sherlinе in tubulin-enriched extracts of proteins from the samples. Measurement of light scattering during the polymerization of the tubulin was carried out using the nephelometric method at a wavelength of 450-550 nm. There was a significant decrease in colchicine-binding activity and the rate of tubulin polymerization in the prefrontal cortex in both diseases, and in VD to a greater extent than in schizophrenia. The obtained results suggest that not only in Alzheimer's disease, but also in other mental diseases such as schizophrenia and VD, there is a decrease in the level of tubulin in the prefrontal cortex of the brain, although to a lesser extent than in Alzheimer's disease, and consequently the amount of microtubules.

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Effect of oxygen implantation on the corrosion-electrochemical behavior of Cu-Mn alloy

Physics and Chemistry of Materials Treatment ◽

10.30791/0015-3214-2020-1-5-13 ◽

2020 ◽

pp. 5-13

Author(s):

V.L. Vorobiev ◽

◽

O.R. Bakieva ◽

F.Z. Gilmutdinov ◽

А.А. Kolotov ◽

...

Keyword(s):

Electrochemical Behavior ◽

Oxygen Implantation ◽

Effect Of Oxygen ◽

Corrosion Electrochemical Behavior

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Corrosion-electrochemical behavior of β-W based CVD coatings in NaCl solution

Corrosion Materials Protection ◽

10.31044/1813-7016-2019-0-12-29-32 ◽

2019 ◽

pp. 29-32

Author(s):

V.V. Dushik ◽

◽

G.V. Redkina ◽

N.V. Rozhanskii ◽

T.V. Rybkina ◽

...

Keyword(s):

Electrochemical Behavior ◽

Nacl Solution ◽

Corrosion Electrochemical Behavior

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ELECTROCHEMICAL BEHAVIOR OF B30 Cu-Ni ALLOY WITH SUPER-HYDROPHOBIC SURFACE IN 3.5%NaCl SOLUTION

ACTA METALLURGICA SINICA ◽

10.3724/sp.j.1037.2011.00470 ◽

2012 ◽

Vol 48 (1) ◽

pp. 94

Author(s):

Qunjie XU ◽

Xianqin DENG ◽

Hongtao PAN ◽

Hong YUN

Keyword(s):

Electrochemical Behavior ◽

Hydrophobic Surface ◽

Nacl Solution ◽

Ni Alloy

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Study of Electrochemical Behavior of Some Dental Alloys

Revista de Chimie ◽

10.37358/rc.18.6.6377 ◽

2018 ◽

Vol 69 (6) ◽

pp. 1598-1602

Author(s):

Alice Arina Ciocan Pendefunda ◽

Constanta Mocanu ◽

Doriana Agop Forna ◽

Cristina Iordache ◽

Elena Luca ◽

...

Keyword(s):

Oral Cavity ◽

Electrochemical Behavior ◽

Base Alloy ◽

Artificial Saliva ◽

Surface Condition ◽

Continuous Process ◽

Metal Alloys ◽

Alloy Surface ◽

Dental Alloys ◽

Dental Restorations

The purpose of the study is to investigate the electrochemical behavior of two dental alloys: palladium alloy (Palidor) and Ni-Cr alloy (Verasoft) in three types of artificial saliva. Determination of corrosion potential and recording of linear and cyclic polarization curves were performed with PGP201 potentiostat (VoltaLab 21- Radelkis Copenhagen. In order to study the modifications produced on the surface of the electrodes, a complex optical microscope MC 1 research type (IOR, Romania) was used, adapted to a digital camera, which was connected to a computer for the digital acquisition of images . Two metal alloys based on Ag-Pd and Ni-Cr were used for the experiments. The materials used came from different types of dental restorations removed from the oral cavity of the patients after a 5-15 years period. As corrosion environments, three artificial saliva were used: Fusayama, Afnor and Rondelli. The Pd-Ag dental alloy exhibits a very good corrosion resistance and the treatment in the Afnor saliva does not affect the surface of the alloy. Electrochemical behavior in Fusayama-Meyer�s saliva of the alloy surface results in a series of spots representing deposits of insoluble salts resulting from the oxidation process, while in the Rondelli saliva there is a series of small corrosion points on the alloy surface. The behavior of the Verasoft alloy in the Afnor and Rondelli saliva is similar; In both solutions, the potential breakthroughs are very close, but in Fusayama-Meyer�s saliva, the potential for initiation of corrosion points is very low (206 mV), a potential that can be encountered in the oral cavity. All metals and metal alloys, even the noble and semi-precious ones, are susceptible to corrosion, forming compounds with properties different from those of the metal or base alloy, which change their surface condition. Metallic dental restorations are permanently affected by the factors of the oral environment (physical-mechanical, chemical and biological), being subjected to a continuous process of degradation.

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Polymerization of acrylonitrile initiated by peroxomonosulphate-thiols redox systems

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19902001 ◽

1990 ◽

Vol 55 (8) ◽

pp. 2001-2007

Author(s):

Gurusamy Manivannan ◽

Pichai Maruthamuthu

Keyword(s):

Ionic Strength ◽

Thermodynamic Parameters ◽

Thermal Polymerization ◽

Reaction Scheme ◽

Degree Of Polymerization ◽

Reducing Agent ◽

Redox Systems ◽

Temperature Range ◽

Rate Of Polymerization

Aqueous thermal polymerization of acrylonitrile (AN) initiated by peroxomonosulphate (HSO5-, PMS)-thiolactic acid (TLA) and PMS-thiomalic acid (TMA) redox systems has been carried out in the temperature range 30-50 °C. The effect of concentration of monomer, initiator, reducing agent, H+, and ionic strength on rate of polymerization, Rp, has been investigated under deaerated conditions. The Rp has been found to depend on, Rp ~ [AN]01.5 [PMS]0.5 [TLA]0.5 in PMS-TLA system and, Rp ~ [AN]02.0 [PMS]1.0 [TMA]0 in PMS-TMA system. The degree of polymerization (Xn) values and thermodynamic parameters have been evaluated. Suitable reaction scheme has been proposed and expressions for Rp and Xn have been obtained.

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