Analysis Of Voltammograms Research Articles

Thermochemical Evaluation of Standard Electrode Potential and Gibbs Energy of Formation of PuCl3 in LiCl-KCl Eutectic Melt

This paper deals with the estimation of and of the Pu Pu redox couple in LiCl-KCl eutectic melt using statistical data fitting of experimental data. The value was also estimated in our laboratory at 723 and 773 K using logarithmic analysis of semi-integral voltammograms and chronopotentiograms. From semi-integral curves, was found to be −2.888 0.021 and −2.810 0.021 V at 723 and 773 K, respectively, whereas it was −2.851 0.020 V at 773 K from the analysis of chronopotentiograms. Based on subsequent statistical analysis, we recommend the following expressions for and applicable for the temperature range 673 to 823 K: and The value in LiCl-KCl eutectic melt was estimated from calculated for the reaction using FactSage package, and it was expressed as

Integrated quality research of domestic special vodka

This article is devoted to complex research of quality and safety performance for special vodka TM «Pervak home Rye». In the course of the analytical study analyzed the regulations governing the quality of special vodka in Ukraine. Evaluation of packaging and labeling of special vodka TM «Pervak home Rye» found that bottle, which poured special vodka protects the product from the negative impact of environmental factors on the quantitative and qualitative losses, and information labeling that printed on packaging contain full information about the product and meet the requirements of ISO 4256:2003. Making special organoleptic evaluation of vodka TM «Pervak home Rye» conducted by tasting the sample, as a result of which found that the sample meets ISO 4256:2003 organoleptic characteristics. The results of evaluation of physical and chemical indicators of quality for special vodka TM «Pervak home Rye», made with alcohol «Lux», showed that strength, alkalinity, aldehydes mass concentration, fusel oil mass concentration, esters mass concentration, volume fraction of methanol match the requirements of ISO 4256:2003. Particular attention is paid to research safety parameters such as heavy metals (cadmium, lead, copper and zinc) using voltammetry. Analysis of sample voltammograms of special vodka TM «Pervak home Rye» showed that the content of heavy metals for special vodka TM «Pervak home Rye» meets the requirements of ISO 4256:2003. As a result of a comprehensive study of special vodka TM «Pervak home Rye» production of «UDC» we can say that it is a high quality and safe for consumption.

Significance of Surface Trivalent Manganese in the Electrocatalytic Activity of Water Oxidation in Undoped and Doped MnO2 Nanowires

AbstractThe oxygen‐evolution reaction (OER) is a bottleneck reaction because of a significant overpotential loss in water electrolysis. Currently, MnO2‐based materials are promising candidates for OER electrocatalysts owing to their abundance and excellent properties. Herein, a hydrothermal method was used to prepare MnO2 nanowires with different diameters. Furthermore, an impregnation method was applied to dope MnO2 nanowires with Ca and Ag ions. Characterization by TEM, XRD, Raman, X‐ray photoelectron spectroscopy (XPS), N2 adsorption, and linear‐scanning voltammogram analysis were performed on these materials. It was found that the OER activity of as‐prepared and doped MnO2 nanowires is highly dependent on the fraction of surface trivalent manganese in MnO2 nanowires. Density functional theory calculations of doped MnO2 revealed the delicate change of the electronic properties of MnO2 nanowires after doping.

Synthesis, Characterization, Optical and Electrochemical Properties of Multinuclear Cobaltadithiolene Complex Derivatives

Four new multinuclear cobaltadithiolene complex derivatives [Cp*CoFe2(CO)6(η2, μ3-S2C6H2(SC3H7)2)] 1, [Fe (CpPPh2)2(Cp*CoS2C6H2(SC3H7)2)2] 2, [Cp*CoRu (CO)3(CH2=CHCH2) (η2,μ2-S2C6H2(SC3H7)2)] 3 and [Cp*Co (NSO2C6H4CH3)(S2C6H2(SC3H7)2)] 4 were obtained by reaction of mono-nuclear cobaltadithiolene complex [Cp*CoS2C6H2(SC3H7)2] (Cp*=C5(CH3)5) with Fe3(CO)12, Fe (CpPPh2)2 (1,1'-bis (diphenylphosphino) ferrocene), Ru (CO)3(CH2=CHCH2)Br, C6H5I= NSO2C6H4CH3(p) (N-(Phenyliodonio)-p-toluene sulfonamidate), respectively. All new complexes were characterized by C/H analysis, 1H NMR, MS and IR spectroscopy. Furthermore, the optical and electrochemical properties of some complexes were also determined by UV-Vis spectra and cyclic voltammogram (CV) analysis.

Synthesis, Characterization and Properties of Arylamine-Acetylene Bridged Tetrahedral Cobalt and Iron Carbonyl Clusters

Four new arylamine-acetylene bridged tetrahedral iron and cobalt carbonyl clusters, [Co2(CO)4(μ-CO)2(η2, μ-TMSCCPh)2N 1, [Fe2(CO)6(μ-CO)(η2, μ-TMSCCPh)NH(PhCC TMS)] 2, [(Co2(CO)6(η2, μ-TMSCCPh))3 3 and [(Fe2(CO)6(μ-CO)(η2, μ-TMSCCPh))2N(Ph CCTMS)] 4, were obtained by reactions of Co2(CO)8 and Fe3(CO)12 with the bis [4-((trimethylsilyl) ethynyl) phenyamine and tris [4-((trimethylsilyl) ethynyl) phenyamine compounds in suitable solvent, respectively. All clusters are confirmed by C/H elemental analysis, MS, 1HNMR and FT-IR spectroscopy. Furthermore, the electrochemical and optical properties of some clusters were also determined by cyclic voltammogram (CV) analysis and UV-Vis spectra.

Novel Thienyl-dibenzothiophene Oligomers End-capped by Hexylphenyl Groups as Potential Organic Semiconductor Materials

Novel thienyl-dibenzothiophene oligomers end-capped by hexylphenyl groups, 2,8-bis[5-(4-n-hexylphenyl)-2-thienyl]dibenzothiophene (28HPTDBT) and 3,7-bis[5-(4-n-hexylphenyl)-2-thienyl]dibenzothiophene (37HPTDBT), have been synthesized using Stille cross-coupling reactions. Newly synthesized oligomers were investigated by Ultraviolet-visible (UV-vis) and photoluminescence (PL) spectroscopy, cyclic voltammogram, and thermal analysis. Strong intermolecular π-π interactions, appropriate energy band gaps and low HOMO energy levels imply that the two oligomers are promising candidate materials for durable organic electronic devices.

Influence of Axial Ligands on Diverse Properties in Three Trinickel String Complexes

Three new trinickel string complexes, [Ni3(dpa)4(3-nba)2](1), [Ni3(dpa)4(4-nba)2]·(CH3OH) (2), and [Ni3(dpa)4(3,5-dnba)2](3) where dpa− is the anion of 2,2′-dipyridylamine, 3-nba− is 3-nitrobenzoate anion, 4-nba− is 4-nitrobenzoate anion, and 3,5-dnba− is 3,5-dinitrobenzoate anion, were synthesized in good yield and characterized by X-ray crystallography, infrared spectra, elemental analysis, magnetic susceptibility, cyclic voltammogram (CV), UV-vis spectra, fluorescence spectra, and TG analysis. The magnetic susceptibilities suggested that the terminal Ni atoms in all three complexes are in high-spin state while the central Ni atom is in a low-spin state. The CVs of complexes 1–3 showed reversible one-electron redox waves at E1/2 = 1.1395 V for 1, 1.108 V for 2, and 1.109 V for 3 corresponding to Ni3 7+/Ni3 6+. The Ni-Ni distances in three complexes are somewhat different, indicating the axial nitrobenzoate ligands have significant effect on the structural assembly. Supplemental materials are available for this article. Go to the publisher's online edition of Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry to view the supplemental file.

Investigation of flexible electrodes modified by TiN, Pt black and IrO x

TiN, platinum (Pt) black and iridium oxide are introduced to the stimulating sites to improve the performance of the flexible electrode. Low temperature process is used to fabricate the modifying films. TiN is coated on the gold sites by magnetron sputtering while platinum black and iridium oxide are coated by electroplating and electrodeposition, respectively. The impedance of the electrode decreases dramatically after modification. The combined analysis of surface morphology and cyclic voltammograms (CV) in phosphate buffer saline (PBS) solution indicates that the modified electrode sites have larger electrode-electrolyte capacitance and smaller faradic resistance than unmodified sites, thus they have smaller electrochemical impedances.

Promazine π-mers formation at a 1,2-dichloroethane/water interface

The behavior of promazine in 1,2-dichloroethane was studied using cyclic voltammetry at the ITIES and UV–vis spectrophotometry. The analysis of voltammograms and spectra obtained varying promazine concentration, pH, nature and concentration of organic electrolyte and applying positive polarisation at the interface allowed us to postulate a reaction scheme consisting in a first step of promazine partition to organic phase, followed by a charge transfer complex (CTC) formation with 1,2-dichloroethane. This CTC induces the oxidation of promazine to the corresponding radical cation which is stabilised in organic phase by π-mers formation. π-mer complexes form ion pairs with the anions of the organic base electrolyte. Similar results were found using methotrimeprazine, another phenothiazine derivative, with a methoxyl group attached to the ring. Chlorpromazine, triflupromazine, perphenazine and fluphenazine were stable in 1,2-dichloroethane.

Electrochemistry of fluoren-9-one based conjugated copolymers: Analysis of voltammograms and correlation with spectroscopic data

Voltammetric and spectroscopic data for novel copolymers of fluoren-9-one with benzene, thiophene, and furan have been used to explore the relationship between the formal potentials and optical band gaps of conjugated polymers. It is shown that the optical band gap measured from the onset of absorption corresponds to the difference in the formal potentials for n- and p-doping. Voltammograms have been analyzed to establish how formal potentials should be defined for these and other conjugated polymers.

Channel Microband Electrode Arrays for Mechanistic Electrochemistry. Two-Dimensional Voltammetry: Electrode Kinetics

The theory of “two-dimensional voltammetry” using arrays of gold channel microband electrodes ranging in size from the millimeter to the micrometer scale is extended to permit the deduction of electrochemical rate constants through the analysis of hydrodynamic voltammograms as a function of both electrode size and electrolyte flow rate (convection). The technique is applied to the reduction of p-chloranil and the oxidation of 2,3,7,8-tetramethoxythianthrene both in acetonitrile solution and electrochemical rate constants are reported.

The mechanism of the electrode reaction of solvated electrons in hexamethylphosphoric triamide

Summary The mechanism of the electrolytic oxidation of solvated electrons in hexamethylphosphoric triamide was investigated by the potential sweep method and hydrodynamic voltammetry. Two waves were attributed to the oxidation of solvated electrons: the first wave, the oxidation of free solvated electrons, and the second wave, the direct oxidation of ion pairs composed of free solvated electrons and sodium ions. Through the analysis of the steady hydrodynamic voltammograms, it was found that the electron transfer process of free solvated electrons was preceded by the dissociation process of ion pairs. The dissociation constant of the ion pair was estimated to be about 2×10 −2 mol l −1 at 5° C.