Journal articles: 'VOLTAMPEROMETRY'

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Shtefan, Viktoriia, Anastasiia Yepifanova, Oleksandr Kobziev, and Myroslava Metenkanych. "VOLTAMPEROMETRY OF Co–Mo ALLOY DEPOSITION." Bulletin of the National Technical University "KhPI". Series: Chemistry, Chemical Technology and Ecology, no. 39 (December 19, 2018): 80–83. http://dx.doi.org/10.20998/2079-0821.2018.39.15.

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HAMAM, A., D. OUKIL, A. DIB, H. HAMMACHE, L. MAKHLOUFI, and B. SAIDANI. "POLYPYRROLE COATED CELLULOSIC SUBSTRATE MODIFIED BY COPPER OXIDE AS ELECTRODE FOR NITRATE ELECTROREDUCTION." Surface Review and Letters 22, no. 05 (2015): 1550065. http://dx.doi.org/10.1142/s0218625x15500651.

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The aim of this work is to synthesize polypyrrole (PPy) films on nonconducting cellulosic substrate and modified by copper oxide particles for use in the nitrate electroreduction process. Firstly, the chemical polymerization of polypyrrole onto cellulosic substrate is conducted by using FeCl 3 as an oxidant and pyrrole as monomer. The thickness and topography of the different PPy films obtained were estimated using a profilometer apparatus. The electrochemical reactivity of the obtained electrodes was tested by voltamperometry technique and electrochemical impedance spectroscopy. Secondly, the modification of the PPy film surface by incorporation of copper oxide particles is conducted by applying a galvanostatic procedure from a CuCl 2 solution. The SEM, EDX and XRD analysis showed the presence of CuO particles in the polymer films with dimensions less than 50 nm. From cyclic voltamperometry experiments, the composite activity for the nitrate electroreduction reaction was evaluated and the peak of nitrate reduction is found to vary linearly with initial nitrate concentration.

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Ilnicka, Anna, Malgorzata Skorupska, Piotr Romanowski, Piotr Kamedulski, and Jerzy P. Lukaszewicz. "Improving the Performance of Zn-Air Batteries with N-Doped Electroexfoliated Graphene." Materials 13, no. 9 (2020): 2115. http://dx.doi.org/10.3390/ma13092115.

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The constantly growing demand for active, durable, and low-cost electrocatalysts usable in energy storage devices, such as supercapacitors or electrodes in metal-air batteries, has triggered the rapid development of heteroatom-doped carbon materials, which would, among other things, exhibit high catalytic activity in the oxygen reduction reaction (ORR). In this article, a method of synthesizing nitrogen-doped graphene is proposed. Few-layered graphene sheets (FL-graphene) were prepared by electrochemical exfoliation of commercial graphite in a Na2SO4 electrolyte with added calcium carbonate as a separator of newly-exfoliated FL-graphene sheets. Exfoliated FL-graphene was impregnated with a suspension of green algae used as a nitrogen carrier. Impregnated FL-graphene was carbonized at a high temperature under the flow of nitrogen. The N-doped FL-graphene was characterized through instrumental methods: high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy. Electrochemical performance was determined using cyclic voltamperometry and linear sweep voltamperometry to check catalytic activity in ORR. The N-doped electroexfoliated FL-graphene obeyed the four-electron transfer pathways, leading us to further test these materials as electrode components in rechargeable zinc-air batteries. The obtained results for Zn-air batteries are very important for future development of industry, because the proposed graphene electrode materials do not contain any heavy and noble metals in their composition.

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Kuzmak, A. E., and A. V. Kozheurov. "Comparative Testing of Corrosive Kinetics of Steel by Voltamperometry and Coulometry Methods." Innovations in Corrosion and Materials Science (Formerly Recent Patents on Corrosion Science) 8, no. 2 (2019): 113–17. http://dx.doi.org/10.2174/2352094908666181106114933.

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Kolesnichenko, I. I., L. M. Balachova, and E. P. Kantarzhi. "Express Screening of Biological Objects Using Multisensor Stripping Voltamperometry with Pattern Recognition." American Journal of Analytical Chemistry 07, no. 07 (2016): 588–96. http://dx.doi.org/10.4236/ajac.2016.77054.

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Hamani, H., D. Lahcene, C. Boufeldja, et al. "Study of Fouling of a Cation Exchange Membrane with a Surfactant Using Voltamperometry." Separation Science and Technology 46, no. 15 (2011): 2322–31. http://dx.doi.org/10.1080/01496395.2011.595031.

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Kot, Iwona, and Halina Krawiec. "Improvement of the Corrosion Resistance of Biomedical Magnesium Alloys in the Ringer’s Solution Using Protective Coatings." Solid State Phenomena 227 (January 2015): 459–62. http://dx.doi.org/10.4028/www.scientific.net/ssp.227.459.

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The corrosion resistance of magnesium alloys depends on their microstructure, especially the presence of different intermetallic phases and precipitates. In this paper, the electrochemical behaviour of Mg1Ca and Mg1Ca1Si magnesium alloys has been investigated in the Ringer’s solution at 37 °C. In order to improve the corrosion resistance of these magnesium alloys composite coatings were fabricated by modification of a chitosan layer. The coatings were prepared by dip-coating in a chitosan solution and then modified by electrochemical deposition of a layer from a solution containing fluorine ions and water glass. The electrochemical performance of chitosan and chitosan modified coated alloys was evaluated by linear sweep voltamperometry and electrochemical impedance spectroscopy. The coated magnesium alloys possess suitable corrosion behaviour for the application as biodegradable implant material.

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Slepushkin, Vyacheslav V., Yuliya V. Rublinetskaya, Elena Yu Moshchenskaya, and Boris I. Kashkarov. "ACTIVITY AND ACTIVITY COEFFICIENTS OF DISSOLVING PHASE OF HETEROGENEOUS ALLOY UNDER CONDITIONS OF LOCAL VOLTAMPEROMETRY." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 59, no. 2 (2018): 22. http://dx.doi.org/10.6060/tcct.20165902.5148.

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The new expressions for the activity coefficients of dissolving phase and for calibration curves i=f(С) are presented as the result of development of previous studies of an anode dissolution process of heterogeneous alloys at the conditions of local voltammetry.

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Sinelnikova, Yuliya, and Nikolai Uvarov. "The application of zinc citrate for the synthesis of carbon materials." MATEC Web of Conferences 340 (2021): 01042. http://dx.doi.org/10.1051/matecconf/202134001042.

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Zinc citrate was prepared and its thermal decomposition was investigated by methods of thermogravimetric analysis and differential scanning calorimetry. Products of the thermal decomposition were investigated by X-ray diffraction analysis. The decomposition proceeds at temperatures 50 - 420 °C in three stages and leads to the formation of nanocrystalline ZnO with the average grain size of 23 nm. Subsequently, zinc citrate was used as a precursor of ZnO hard template for preparation of carbon mesoporous materials by the solid template method. The carbon materials were obtained by pyrolysis of polymer matrix of phenol-formaldehyde resin in which zinc citrate was added. It was found that the resulting material has a specific surface area of 1051 m2/g. According to the cyclic voltamperometry data, the material has a specific capacity 40 F/g.

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Anzano, Jesús, Roberto-Jesús Lasheras, Beatriz Bonilla, et al. "Determination of trace metals by voltamperometry in zebra mussel (Dreissena polymorpha) employed as environmental bio-indicator." Green Chemistry Letters and Reviews 4, no. 3 (2011): 261–67. http://dx.doi.org/10.1080/17518253.2010.528050.

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Kozina, Iryna, Halina Krawiec, Maria Starowicz, and Magdalena Kawalec. "Corrosion Resistance of MgZn Alloy Covered by Chitosan-Based Coatings." International Journal of Molecular Sciences 22, no. 15 (2021): 8301. http://dx.doi.org/10.3390/ijms22158301.

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Chitosan coatings are deposited on the surface of Mg20Zn magnesium alloy by means of the spin coating technique. Their structure was investigated using Fourier Transform Infrared Spectroscopy (FTIR) an X-ray photoelectron spectroscopy (XPS). The surface morphology of the magnesium alloy substrate and chitosan coatings was determined using Scanning Electron Microscope (FE-SEM) analysis. Corrosion tests (linear sweep voltamperometry and chronoamperometry) were performed on uncoated and coated magnesium alloy in the Hank’s solution. In both cases, the hydrogen evolution method was used to calculate the corrosion rate after 7-days immersion in the Hank’s solution at 37 °C. It was found that the corrosion rate is 3.2 mm/year and 1.2 mm/year for uncoated and coated substrates, respectively. High corrosion resistance of Mg20Zn alloy covered by multilayer coating (CaP coating + chitosan water glass) is caused by formation of CaSiO3 and Ca3(PO4)2 compounds on its surface.

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Kozaderov, O. A., and A. V. Vvedenskii. "Voltamperometry of selective dissolution of Ag-Au alloys under conditions of solid phase-liquid phase mass transfer." Protection of Metals and Physical Chemistry of Surfaces 49, no. 6 (2013): 724–33. http://dx.doi.org/10.1134/s2070205113060099.

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Kabirova, L. R., Yu A. Yarkaeva, Yu R. Provorova, R. A. Zilberg, A. V. Sidelnikov, and V. N. Maistrenko. "An ACTIVATION APPROACH TO INCREASE OF THE ENANTIO-SELECTIVITY OF COMPOSITE ELECTRODES IN CONDITIONS OF CYCLIC VOLTAMPEROMETRY." Vestnik Bashkirskogo universiteta 7, no. 1 (2018): 95. http://dx.doi.org/10.33184/bulletin-bsu-2018.1.16.

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Sidel’nikov, A. V., V. N. Maistrenko, F. Kh Kudasheva, N. V. Kuz’mina, S. V. Sapel’nikova, and N. G. Gileva. "Voltamperometry of Aromatic Nitro Compounds Using a Multisensor System of Electrodes Modified with Poly(Arylene Phthalide Ketones)." Journal of Analytical Chemistry 60, no. 6 (2005): 508–13. http://dx.doi.org/10.1007/s10809-005-0130-x.

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Martemianov, Dmitrii V., Sergey P. Zhuravkov, Mikhail B. Khaskelberg, Pavel E. Slyadnikov, and Luiza V. Nadeina. "Study of Hematite Mineral Samples in Purification of Aqueous Solutions from As³⁺and Fe³⁺Ions." Key Engineering Materials 712 (September 2016): 295–300. http://dx.doi.org/10.4028/www.scientific.net/kem.712.295.

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Hematite mineral samples of Korshunov deposit were the subject of the study. The samples size was less than 0.1 mm; 0.5-1 mm and 1.5-2.5 mm. Some physicochemical properties of adsorbent samples were investigated: specific surface and specific pore volume were identified; zeta potential was measured; thermal and elemental analyses were carried out. Sorption properties of samples obtained under static conditions were studied. They were investigated in removing Fe3+ and As3+ ions from simulated solutions. Content analysis of the ions in filtrates was carried out by stripping voltamperometry and photocolorimetry methods. In using hematite, removal of As+3 ions from the solution increases if adsorption time increases. The smaller grain size, the better purification of simulated solution was. Hematite with the size of particles less than 0.1 mm is more effective in removing of Fe+3 ions from solution, if contact time is short. It has been found that if contact time is longer, hematite with 0.5-1 mm and 1.5-2.5 mm sizes of particles is better to use. The authors have concluded that hematite can be used for efficient water purification from iron ions and arsenic ions

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Pérez-Bueno, J. J., M. L. Mendoza López, K. M. Brieño Enriquez, J. Ledesma García, L. A. Godínez Mora-Tovar, and C. Angeles Chavez. "Hydrogen Storage Enhancement Attained by Fixation of Ti on MWNTs." Advances in Materials Science and Engineering 2012 (2012): 1–7. http://dx.doi.org/10.1155/2012/801230.

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Nowadays, hydrogen has a preponderant position among the potentially sustainable energy sources. Due to its power density, its storage is of main concern when considering a broad use in practical applications. Carbon nanotubes constitute promising candidates for the design and construction of hydrogen storage devices. This work explores the use of some procedures involving electrochemistry, aimed to bond atomic Ti on the outer surface of MWNTs. Each titanium atom has the potential of hosting two hydrogen molecules and relinquishing them by heating. Nevertheless, nanotubes are difficult to handle due to electrostatic charge and agglomeration, and in this context, two routes were tested as procedures to spread and stick nanotubes on an electrode: (1) a functionalization capable of attaching gold was tested in two forms, as either using 4 nm particles or a flat gold electrode. The fixation of Au particles was confirmed by HRTEM. (2) A simpler route that consisted on drying a CH2Cl2/nanotubes solution previously spread on a glassy carbon flat electrode. CH2Cl2was selected as the medium and TiCl4as the precursor for attaching atomic Ti to the nanotubes. The results revealed that hydrogen adsorption, estimated from voltamperometry, was five times higher on Ti-MWNTs than on bare nanotubes.

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Fijołek, Andrzej, Janusz Lelito, Halina Krawiec, Jagoda Ryba, and Łukasz Rogal. "Corrosion Resistance of Mg72Zn24Ca4 and Zn87Mg9Ca4 Alloys for Application in Medicine." Materials 13, no. 16 (2020): 3515. http://dx.doi.org/10.3390/ma13163515.

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The aim of this work was to monitor the corrosion rate of the Mg72Zn24Ca4 and Zn87Mg9Ca4 alloys. The purity of the alloying elements was 99.9%. The melt process was carried out in an induction furnace. The melting process took place under the cover of an inert gas (argon). The copper form was flooded by liquid alloy. Then, in order to obtain ribbons, the cast alloy, in rod shape, was re-melted on the melt spinning machine. The corrosion resistance of both alloys has been determined on the basis of the following experiments: measurements of the evolution of OCP (open circuit potential), LSV (linear sweep voltamperometry) and EIS (electrochemical impedance spectroscopy). All corrosion tests were carried out in Ringer’s solution at 37 °C and pH 7.2. The corrosion tests have revealed that the zinc alloy, Zn87Mg9Ca4, exhibits significantly higher corrosion resistance in the Ringer solution compared to the magnesium alloy, Mg72Zn24Ca4. Moreover, it has been shown that the cathodic reaction proceeds faster on the surface of ribbons. EIS measurements show that the dissolution of Mg alloy proceeds with two steps: transfer of Mg2+ ions to the Ringer solution and then the formation of the corrosion products, which are deposited on the surface of magnesium alloy. It has been revealed, too, that for both bulk materials, diffusion of chloride ions through the corrosion product’s layer takes place.

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Fiołek, Aleksandra, Sławomir Zimowski, Agnieszka Kopia, Alicja Łukaszczyk, and Tomasz Moskalewicz. "Electrophoretic Co-deposition of Polyetheretherketone and Graphite Particles: Microstructure, Electrochemical Corrosion Resistance, and Coating Adhesion to a Titanium Alloy." Materials 13, no. 15 (2020): 3251. http://dx.doi.org/10.3390/ma13153251.

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The present study explores the possibilities of fabricating a graphite/polyetheretherketone (PEEK) composite coating on a Ti-6Al-4V titanium alloy through duplex treatment consisting of electrophoretic deposition (EPD) and heat treatment. It has been found that the electrophoretic co-deposition of graphite and PEEK microparticles can be performed from environmentally-friendly pure ethanolic suspensions. Zeta potential measurements and a study of the interaction between both particle types with the use of transmission electron microscopy allowed potential mechanisms of particle co-deposition to be indicated. Microstructure characterization was performed on macro-, micro- and nanoscale using visible light microscopy, X-ray diffractometry and electron microscopy. This allowed the coating homogeneity and distribution of graphite particles in the polymer matrix to be described. Graphite particles in the form of graphene nanosheet packages were relatively evenly distributed in the coating matrix and oriented parallel to the coating surface. The heat-treated coatings showed high scratch resistance and no adhesive type destruction was observed, but they were highly susceptible to deformation. The corrosion measurements were performed with use of electrochemical techniques like open circuit potential and linear sweep voltamperometry. The coated alloy indicated better electrochemical corrosion resistance compared with the uncoated alloy. This work showed the high versatility of the electrophoretic co-deposition of graphite and PEEK particles, which combined with post-EPD heat treatment allows composite coatings to be fabricated with controlled distribution of graphite particles.

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Potvin, E., M. Drogowska, H. Ménard, and L. Brossard. "La dissolution anodique du cuivre en présence d'ions F− dans des solutions aqueuses acides." Canadian Journal of Chemistry 65, no. 9 (1987): 2109–13. http://dx.doi.org/10.1139/v87-350.

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The influence of F− ions on the anodic dissolution of copper in aqueous acidic solutions (pH 1.6–6), mainly at pH 5 with 0.1 M KF, has been studied. The nature of the changes that occur on the electrode during the oxidation has been examined by cyclic voltamperometry as well as by different techniques of surface analysis (SEM, XPS, AES). To determine the mechanism of the electrochemical oxidation of copper at pH 5, studies with rotating disk electrodes have been carried out under conditions giving rise to a general dissolution of copper. At pH 1.6–6, the copper electrode dissolves uniformly, i.e., without preferential zones on the surface, when it is submitted to a potentiodynamic polarization (10 mV s−1) at potentials above 0 VECS. At slightly acidic pH (pH 5, KF0.1 M), with a sweep of potential up to +0.5 V, the oxidation of copper begins with a generalized corrosion of the electrode and it is followed by the formation of a film of Cu2O that is not passivating; as the oxidation proceeds, the current drops and the electrode becomes passivated. One model for the anodic dissolution is presented for the results obtained at pH 5. When a uniform corrosion develops on the rotating electrode, the copper is oxidized to Cu2+ ions. When ω → 0, the rate of dissolution of the electrode is limited by the diffusion of the Cu2+ ions from the electrode to the solution, whereas when ω → ∞ the process of charge transfer is the limiting factor to the kinetics of the dissolution. [Journal translation]

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Biletska, Yana, Taisіa Ryzhkova, Anna Perepelytsia, and Andrii Husliev. "INVESTIGATION OF THE CONSERVATION OF VITAMINS AND MICROELEMENTS DURING STORAGE IN BOILED-SMOKED SAUSAGES WITH ENRICHED LEGUMINOUS FLOUR." EUREKA: Life Sciences 3 (May 31, 2020): 26–30. http://dx.doi.org/10.21303/2504-5695.2020.001320.

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There has been studied the conservation of vitamins and microelements in boiled-smoked sausages, using enriched leguminous flour. The research object is boiled-smoked sausages, in which recipes there were used sprout flour of soya and nut that are carriers of vitamins А, Е, С, В6, В9, В12 and microelements, including iodine and selenium, as an enriching ingredient. One of problems for today is an increase of the population with endocrine disorders. It is possible to prevent this problem by timely prophylaxis as consumption of products with iodine. Modern studies in molecular pharmacology have proved that for assimilating iodine by the organism, the “presence” of other nutrients, intensifying its assimilability and being its synergists is needed. The method of inversion voltamperometry and the one of high-effective liquid chromatography were used in the study. It has been established, that sausage products contain in their composition after 30 days of storage vitamins: А – 0.4; Е – 0.3; С – 17; В6 – 0.32; В9 – 0.4; В12 – 0.03, mg/100g. And microelements: Fe – 5.0; Mg – 340, Z – 8.5, Cu – 0.95; Se – 0,026; І – 0,025, mg/100g. That satisfies: 50; 150; 30,9; 150; 200; 100 % of the daily need in vitamins А; Е; С; В6; В9; В12, respectively and 50; 97; 85; 95; 37; 37.5 % of the daily need in microelements Fe; Mg; Z; Cu; Se; І, respectively. Comparing with a control recipe, enriched products have the increased content of nutrients – iodine synergists that provide essential advantages, “covering” deficiency conditions in other substances, needed for iodine assimilation. Let’s assume that it will be an effective prophylaxis for persons with iodine-deficiency diseases

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Nechvoglod, O. V., Evgeny N. Selivanov, and S. V. Mamyachenkov. "Effect of Structure on the Electrochemical Oxidation Rate of Copper and Nickel Sulfides." Defect and Diffusion Forum 326-328 (April 2012): 383–87. http://dx.doi.org/10.4028/www.scientific.net/ddf.326-328.383.

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Synthesized samples were crystallized at 10 - 1000 K/sec (νcooling) to study the effect of sulfides structure on the electrochemical oxidation rates. The methods of X-ray, optical and electronic microscopy are used to analyze the phase composition, and the methods of voltamperometry and chronoamperometry are used to study the laws of electrochemical oxidation. Slow cooling of the samples with sulfide phase (Cu1,96S, Ni3S2) leads to crystallization of the metal (Ni, Cu). High cooling rate leads to crystallization of non-equilibrium phases, increasing of proportion of the sulfide phase and decreasing of metallic component up to complete disappearance. It is shown that electrochemical oxidation of copper and nickel sulfides proceeds stepwise: Me2S Me2-XS Me1+XS MeS Me2+ + S. Experiments have revealed the rates of electrochemical oxidation of granular sulfides that exceed the rates established for the slowly cooled samples. The rates of the electrochemical oxidation of Ni3S2 at potential of 1500 mV are 8.810-8 g/sec·mm2 (at vcooling = 10 К/sec) and 1.310-7 g/sec·mm2 (at νcooling = 1000 К/sec). The rates of the electrochemical oxidation of Cu2S at potential of 1000 mV are 2.810-8 g/sec·mm2 (at νcooling = 10 К/sec) and 4.310-8 g/sec·mm2 (at νcooling = 1000 К/sec). It is found that the forming of a passivation layer effects the rate of the electrochemical oxidation of copper sulfide and nickel sulfide. Non-equilibrium phase composition and refinement provide greater reactivity of sulfides in the conditions of anodic polarization. The oxidation and passivation of metallic phase along with sulfide phases proceed from the surface of Me2S Me alloys. As for the samples crystallized at 1000 K/sec only anodic oxidation of sulfides occurs due to a lack of metallic phase. The compositions of passivation films and potentials providing the extraction of sulfur in the elemental state from the sulfides crystallized at high rates were determined.

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Martynov, A. I., N. I. Il'ina, Lyudmila Vasil'evna Luss, et al. "Features ofpollen in region of chemical factor influence." Russian Journal of Allergy 8, no. 6 (2011): 12–16. http://dx.doi.org/10.36691/rja772.

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Background. To study features of cereal grasses pollen collected in region were the enterprise that is in charge of destruction of the chemical weapons is placed - Gorniy, Saratov region. Materials and methods. Object of the research was pollen of cereal grasses collected in regions, differed by the ecological characteristics: object for destruction of chemical weapon of Gorniy of the Saratov region (investigated region), Privolzhsky area of the Ivanovo area (ecologically favorable region) and near to а motorway, Istrinsky area of Moscow Region (ecologically unfavorable region). Definition of the maintenance of heavy metals in pollen of grasses was carried out by the method of invertion voltamperometry, by percentage of sprouted pollen grains and the morphological characteristics of pollen grains by microscopy. Results. In samples of pollen collected within object for destruction of the chemical weapon of Gorniy, the maintenance of lead, mercury, zinc and cadmium, in comparison with non-polluting area, and with average values across the Russian Federation, thus lead almost ten times above, in comparison with average values of the maintenance in plants across the Russian Federation is authentically increased. The morphological changes of pollen more expressed in ecologically adverse region are revealed: the quantity of abortive pollen grains near to а motorway was above more than ten times, and, within the enterprise for the object for destruction of the chemical weapon of Gorniy, almost in 3 times, in comparison with non-polluting region. It is established that along with heavy metals (lead and zinc) which are а part of the list of the harmful substances containing in emissions in atmosphere of the enterprise for the object for destruction of the chemical weapon of Gorniy, the increasing of mercury and cadmium levels which are absent in а production cycle is revealed and can t be connected with enterprise functioning. Possibly other sources of pollution render.on the mercury and cadmium maintenance . Conclusion. Thus, in experiments it has been shown that pollen of plants possesses considerable sorbtion capacity for the heavy render metals which are а part of harmful production factors which change bioindicator properties of plant pollen and could form hypersensitivity.

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Espinoza Montero, Patricio J., and Bernando A. Fontana Uribe. "Estudio Comparativo de los Parámetros Cinéticos del Sistema Fe(CN)6 3-/4- en Carbón Vítreo y Diamante Dopado con Boro, Mediante Voltamperometría de Corriente Muestreada y Disco Rotatorio." Química Central 3, no. 2 (2017): 19–24. http://dx.doi.org/10.29166/quimica.v3i2.1209.

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Se llevó a cabo un estudio comparativo de los parámetros cinéticos tanto para la oxidación como para la reducción del sistema redox Fe(CN)6 3-/4- en un electrodo de disco rotatorio de diamante dopado con boro (RDE-BDD, por siglas en inglés) y un electrodo de disco rotatorio de carbón vítreo (RDE-VC, por sus siglas en inglés) mediante voltamperometría lineal y voltamperometría de corriente muestreada, y se compararon ambas técnicas. Los resultados encontrados muestran que las dos técnicas son complementarias para sistemas cuasi-reversibles. Además, los resultados obtenidos sobre un electrodo de BDD se compararon con datos informados en la literatura reportados mediante voltamperometría cíclica en régimen estacionario. Se demostró la importancia del control de transferencia de masa durante los experimentos de estudio cinético del sistema en estudio.

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Abadía López, Julieth, Claudia L. Pérez Valdés, and Mario Grajales Tamayo. "Electroquímica de Oro en Ácido Clorhídrico." Revista de Ciencias 13 (September 4, 2011): 93–104. http://dx.doi.org/10.25100/rc.v13i0.647.

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Se investigó la electroquímica del oro en soluciones clorhídricas ácidas usando voltamperometría cíclica y voltamperometría de redisolución anódica. Los resultados demostraron que la disolución del oro y la formación de óxidos de oro ocurren a potenciales por encima de +0.9 V (vs. Ag / AgCl )• La reducción de AuCl4 sobre electrodo de grafito pirolítico rugoso (RPG) procede con adsorción lenta y mostró un pico bien definido a +0.55 V; este pico presentó una pobre resolución con electrodos de platino y carbono vitreo. La HAuCl4 H^PdC^ y HAUCI4 0.45 V durante cuatro minutos (tres de agitación más uno de reposo) y redisolviendo con un barrido lineal desde +0.0 hasta+1.15 V a H2PdCl4 HAuCl4 a-0.28 V, se depositan simultáneamente Au, Pd y una aleación Au-Pd. A 0.45 V únicamente se deposita Au. La voltamperometría de redisolución anódica fue aplicada con buenos resultados a la determinación de oro en lixiviados clorhídricos provenientes de la precipitación de platino como (NH4)2PtCl6.

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Desbene-Monvernay, Annie, Ouzama Karazoun, Jacques Berthelot, and Paul-Louis Desbene. "Modelisation de la bromation au moyen de TBABr3 de matrices organiques complexes: suivi de la bromation de carbazoles à l'aide de la voltampérométrie et de la chromatographie liquide hautes performances." Canadian Journal of Chemistry 70, no. 3 (1992): 870–76. http://dx.doi.org/10.1139/v92-115.

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To determine the degree of substitution of complex matrices, the bromination of various carbazoles by tetrabutylammonium tribromide has been used as a model of a substitution reaction. This has allowed us to test the validity of the voltamperometric titration of tribromide ions and species formed (Br− and H+ ions). The results obtained for various substrate/reagent ratios are in excellent agreement with those of high performance liquid chromatography. The electrochemical titration can be considered as reliable, fast, and very easy to use. It permits us to follow the bromination kinetics and to determine the degree of substitution of complex organic matrices. Keywords: bromination, tetrabutylammonium tribromide, voltamperometric titration (Br3−, Br−, H+), degree of substitution.

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Kupchyk, Olena. "STRIPPING VOLTAMPEROMETRIC DETERMINATION OF HEAVY METALS IN HONEY SAMPLES." Chemistry & Chemical Technology 11, no. 3 (2017): 285–90. http://dx.doi.org/10.23939/chcht11.03.285.

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Krulic, D., N. Larabi, and N. Fatouros. "Voltamperometric study of the titanium IV–oxalate complexes." Journal of Electroanalytical Chemistry 579, no. 2 (2005): 239–42. http://dx.doi.org/10.1016/j.jelechem.2005.02.010.

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Hernández-Albors, Alejandro, Gloria Colom, J. Pablo Salvador, and M. Pilar Marco. "Studies towards hcTnI Immunodetection Using Electrochemical Approaches Based on Magnetic Microbeads." Sensors 18, no. 8 (2018): 2457. http://dx.doi.org/10.3390/s18082457.

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Different electrochemical strategies based on the use of magnetic beads are described in this work for the detection of human cardiac troponin I (hcTnI). hcTnI is also known as the gold standard for acute myocardial infarction (AMI) diagnosis according to the different guidelines from the European Society of Cardiology (ESC) and the American College of Cardiology (ACC). Amperometric and voltamperometric sandwich magnetoimmunoassays were developed by biofunctionalization of paramagnetic beads with specific antibodies. These bioconjugates were combined with biotinylated antibodies as detection antibodies, with the aim of testing different electrochemical transduction principles. Streptavidin labeled with horseradish peroxidase was used for the amperometric magnetoimmunoassay, reaching a detectability of 0.005 ± 0.002 µg mL−1 in 30 min. Cadmium quantum dots-streptavidin bioconjugates were used in the case of the voltamperometric immunosensor reaching a detectability of 0.023 ± 0.014 µg mL−1.

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Romero Bonilla, Hugo Ítalo, Jazmín Carolina Chiriboga Cabrera, and Alisson Paola Siguenza Balladares. "DETERMINACIÓN DE ULTRATRAZAS DE CADMIO (II) POR TÉCNICAS VOLTAMÉTRICAS CON ELECTRODO DE CARBÓN VÍTREO MODIFICADO CON PELÍCULA DE BISMUTO." Revista de la Sociedad Química del Perú 84, no. 1 (2018): 57–67. http://dx.doi.org/10.37761/rsqp.v84i1.165.

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El objetivo de este trabajo consistió en la determinación de ultratrazas de cadmio mediante la técnicas voltamétricas, modificando un electrodo de carbón vítreo con película de bismuto (BiFE). in situ con un potencial de pre-concentración Eprec=-1,2V y un tiempo de deposición de tprec= 100s en medio de acetato de sodio/ácido acético 0,1M (pH 4,5) en ausencia de oxígeno, mediante voltamperometría de barrido lineal (LSV) con concentraciones en intervalos de 100-800 μg.L-1 y 2-10mg.L-1 y voltamperometría de onda cuadrada (SWV) con concentraciones entre 50-800μg.L-1. Se obtuvieron voltamogramas de potencial vs intensidad de la corriente y gráficos de concentración vs intensidad de la corriente, con linealidades de 0,997, 0,992 y 0,997 respectivamente. Se observó mejor sensibilidad en SWV observando picos más pronunciados tanto para cadmio y bismuto, ubicándose los potenciales de oxidación de cadmio para LSV en -0,701V, -0,68V y SWV en -0,701V, respectivamente.

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Gładysz, O., and P. Skibiński. "Voltamperometric test of ephedrine on a gold disc microelectrode." Materials Chemistry and Physics 246 (May 2020): 122792. http://dx.doi.org/10.1016/j.matchemphys.2020.122792.

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Abuzwida, M. A., A. G. Maslennikov, and V. F. Peretrukhin. "Voltamperometric determination of uranium and plutonium in alkaline solutions." Journal of Radioanalytical and Nuclear Chemistry Articles 147, no. 1 (1991): 41–50. http://dx.doi.org/10.1007/bf02039564.

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Ballesteros, Y., M. J. Gonzalez de la Huebra, M. C. Quintana, P. Hernandez, and L. Hernandez. "Voltamperometric determination of kinetin with a carbon paste modified electrode." Microchemical Journal 74, no. 2 (2003): 193–202. http://dx.doi.org/10.1016/s0026-265x(03)00022-5.

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Demidov, O. P., А. A. Bumber, I. A. Profatilova, et al. "VOLTAMPEROMETRIC INVESTIGATION OF 1,3-DIAZAPYRENES AND 2-(2-NAPHTHYL)QUINOLINE." Vestnik Yuzhnogo nauchnogo tsentra 3, no. 3 (2007): 28–31. http://dx.doi.org/10.23885/1813-4289-2007-3-3-28-31.

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Hilding-Ohlsson, Astrid, Jonathan A. Fauerbach, Natalia J. Sacco, M. Celina Bonetto, and Eduardo Cortón. "Voltamperometric Discrimination of Urea and Melamine Adulterated Skimmed Milk Powder." Sensors 12, no. 9 (2012): 12220–34. http://dx.doi.org/10.3390/s120912220.

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Echeverry, Carlos A., Alexis Tigreros, Alejandro Ortiz, Braulio Insuasty, and Nazario Martín. "Free-base tetraarylporphyrin covalently linked to [60]fullerene through ethynylfluorene spacer." Journal of Porphyrins and Phthalocyanines 15, no. 11n12 (2011): 1231–38. http://dx.doi.org/10.1142/s1088424611004257.

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The synthesis, structural and electronic characterization of novel electroactive systems based on porphyrin-fullerene in which the chromophores are linked by an ethynylfluorene spacer unit is reported. Sonogashira couplings have been used in short and efficient sequences to give access to these new molecules on a practical scale. The absorption studies, voltamperometric measurements and theoretical calculations at DFT level reveal the push-pull behavior for these systems.

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Nagles, Edgar O., Roxana Ríos, John Hurtado, and Verónica Arancibia. "Estudio electroquímico de Rojo de Pirogalol (RP) en presencia de surfactantes de diferente carga." Ingenium 6, no. 13 (2012): 65. http://dx.doi.org/10.21774/ing.v6i13.89.

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La interacción de Rojo de Pirogalol (RP) con los surfactantes dodecil sulfato de sodio (SDS) y bromuro de cetilpiridinio (CPB) de carga negativa y positiva respectivamente fue estudiada por voltamperometría cíclica a pH 2,0 y 8,0 sobre electrodos serigrafiados de carbono. Su interacción y localización en los surfactantes fue estudiada por los cambios sufridos en las corrientes de pico a diferentes concentraciones de surfactantes observándose efectos catalíticos de corriente.

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Pelado, Beatriz, Julieta Coro, Pilar de la Cruz, and Fernando Langa. "Free-base porphyrin and [60]fullerene linked by oligomeric ethylenedioxythienylenevinylene bridge." Journal of Porphyrins and Phthalocyanines 19, no. 01-03 (2015): 404–10. http://dx.doi.org/10.1142/s1088424615500261.

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The synthesis and structural characterization and the study of the electronic properties of two novel porphyrin-bridge-fullerene molecules, where a free-based porphyrin and [60]fullerene are connected through one and two units of ethylenedioxythienylenevinylene π-conjugated bridges, is reported. The absorption studies, voltamperometric measurements and theoretical calculations at DFT level are presented. A HOMO–LUMO gap as low as 1.41 eV has been found for compound 6.

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Romero-Bonilla, Hugo Ítalo, Thalía Gabriela Vera-Infante, Jennifer Del Cisne Jumbo-Sari, Freddis Franco Pesantez, and Felipe Fernando Redrovan-Pesantez. "APLICACIÓN DE VOLTAMPEROMETRÍA DE REDISOLUCIÓN ANÓDICA PARA LA DETERMINACIÓN DE ANTIMONIO." Revista de la Sociedad Química del Perú 85, no. 3 (2019): 293–304. http://dx.doi.org/10.37761/rsqp.v85i3.247.

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Se validó un método voltamétrico para determinar la concentración de antimonio en medio acuoso. Se usó la técnica voltamperométrica de redisolución anódica, utilizando un potenciostato. Se aplicó cronoamperometría a E= -1,2 V durante 50 s. Se aplicó una voltametría de barrido lineal con potenciales entre Ei = -1,2 V y Ef = 0,5 V a una velocidad de 20 mV/s. Esto se llevó a cabo en solución electrolítica H3 PO4 0,5 M, donde se puede observar un incremento en el pico de intensidad de corriente en función de la concentración de las soluciones evaluadas a un potencial de 84,96 mV. Para validar el método se determinó la linealidad, precisión, límite de detección y límite de cuantificación. Se prepararon cuatro concentraciones de antimonio por triplicado, en un rango de 1, 5, 10, 15, 20 mg/L, respectivamente. Se construyó una curva de calibración de concentración experimental expresada como intensidad de corriente (I) vs concentración teórica. La linealidad fue demostrada partiendo del coeficiente de proporcionalidad de 0,9979 con coeficiente de variación (CV) de 18,2 %. El límite de detección y cuantificación tuvieron valores de 1,041 mg/L y 1,718 mg/L, respectivamente.

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Pérez-Cabeza, Susan B., Nicolás Morón Angarita, Martha Cervantes, and Mario A. Barón-Rodríguez. "Evaluación del potencial antioxidante en extracto de espinaca por voltamperometría cíclica." Revista ION 30, no. 2 (2018): 99–105. http://dx.doi.org/10.18273/revion.v30n2-2017009.

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P´érez-Uresta, Nicole, Diego Bolaños-Mendez, Marjorie Montero-Jiménez, Lenys Fernández, Alexis Debut, and Patricio Espinoza-Montero. "CUANTIFICACIÓN ELECTROQUÍMICA DE MERCURIO (II) EN MEDIO ACUOSO SOBRE UN MICROELECTRODO DE FIBRA DE CARBONO MODIFICADO CON NANOPARTÍCULAS DE ORO." infoANALÍTICA 9, no. 1 (2021): 49–66. http://dx.doi.org/10.26807/ia.v9i1.167.

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El mercurio es considerado un contaminante altamente peligroso debido a su elevada toxicidad y a su carácter acumulativo. Presenta varios efectos en la salud humana tales como: trastornos del sistema nervioso, deterioro intelectual, problemas gastrointestinales y cáncer. El uso de técnicas electroquímicas es una alternativa para la cuantificación de mercurio a niveles traza, debido a su bajo costo y buena sensibilidad. En este trabajo de investigación se evaluó un microelectrodo de fibra de carbono modificado con nanopartículas de oro para la determinación de mercurio (II) en medio acuoso. Se realizó la modificación superficial de la fibra de carbono electrodepositando nanopartículas de oro, a un potencial de -0,1 V durante 100 s, y se utilizó microscopía electrónica de barrido y voltamperometría cíclica para confirmar la presencia de nanopartículas de oro. Se cuantificó el mercurio (II) mediante voltamperometría de redisolución anódica de pulso diferencial. Se obtuvo un rango lineal, en la curva de calibración, entre 50 - 100 µg L-1 de mercurio (II). Los límites de detección y de cuantificación obtenidos fueron de 38 y 46 µg L-1, respectivamente. La validación de la metodología se realizó mediante porcentaje de recuperación, obteniendo valores entre 94 y 104 % y desviación estándar relativa (RSD, por sus siglas en inglés) entre 3,6 y 4,7 %. El método propuesto muestra características útiles para su implementación en el monitoreo de contaminación por mercurio.

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Matysik, J., M. Przegalński, and M. Orzechowska. "The dependence of voltamperometric peak height on the range of electrode polarization potentials." Journal of Electroanalytical Chemistry and Interfacial Electrochemistry 191, no. 2 (1985): 431–36. http://dx.doi.org/10.1016/s0022-0728(85)80036-x.

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Bounegru, Alexandra Virginia, and Constantin Apetrei. "Voltamperometric Sensors and Biosensors Based on Carbon Nanomaterials Used for Detecting Caffeic Acid—A Review." International Journal of Molecular Sciences 21, no. 23 (2020): 9275. http://dx.doi.org/10.3390/ijms21239275.

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Caffeic acid is one of the most important hydroxycinnamic acids found in various foods and plant products. It has multiple beneficial effects in the human body such as antioxidant, antibacterial, anti-inflammatory, and antineoplastic. Since overdoses of caffeic acid may have negative effects, the quality and quantity of this acid in foods, pharmaceuticals, food supplements, etc., needs to be accurately determined. The present paper analyzes the most representative scientific papers published mostly in the last 10 years which describe the development and characterization of voltamperometric sensors or biosensors based on carbon nanomaterials and/or enzyme commonly used for detecting caffeic acid and a series of methods which may improve the performance characteristics of such sensors.

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Garcia, Carlos, Hugo Romero, Humberto Ayala, Byron Lapo, Adriana Lam, and Alexander Moreno. "Cuantificación de ácido ascórbico en pimientos comercializados en la zona 7 del Ecuador aplicando voltamperometría." Cumbres 3, no. 2 (2020): 71–83. http://dx.doi.org/10.48190/cumbres.v3n2a7.

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El propósito de la presente investigación, es cuantificar el ácido ascórbico por métodos electroquímicos de pimientos comerciales de la zona 7 del Ecuador, que comúnmente llegan al mercado Mayorista de la ciudad de Machala. Para este análisis se determina la intensidad de corriente reflejada por cada pico de oxidación en micro amperios (µA); requiriéndose la utilización de un electrodo (carbono vítreo, plata Cloruro de plata y platino), en esta experimentación cada una de las muestras se extrae 5 ml. de zumo de pimiento verde, se analiza por triplicado con la adición de un electrolito de NaNO3/HNO30,1M y una solución patrón de ácido ascórbico en orden ascendente (5, 12, 17, 25, 35 ml.). Mediante el Potenciostato se obtiene lecturas de picos de intensidad de corriente, se elaboró una curva de calibración, obtuvimos resultados de concentración, se aplica el método estadístico de regresión lineal ANOVA (análisis de varianza de un factor), los resultados obtenidos muestran diferencias significativas superiores de concentración de AsA en pimientos verdes de: Sta. Isabel Criollo (82,700 mg/100 g), Arenillas Criollo (101,886 mg/100 g), Lojano Grueso (102,212 mg/100 g), Guayas Grueso (125,954 mg/100 g), Palmales - Salvador (150,296 mg/100 g), Oña Grueso (158,447 mg/100 g), Sta. Isabel Orgánico (174,269 mg/100 g). Con los resultados de la presente investigación se concluye que el pimiento que se comercializa en la zona 7 del Ecuador es una fuente importante de ácido ascórbico capaz de satisfacer las necesidades básicas diarias recomendadas de este antioxidante en la alimentación humana.

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Apetrei, Irina Mirela, and Constantin Apetrei. "Highly sensitive voltamperometric determination of pyritinol using carbon nanofiber/gold nanoparticle composite screen-printed carbon electrode." International Journal of Nanomedicine Volume 12 (July 2017): 5177–88. http://dx.doi.org/10.2147/ijn.s138978.

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Álvarez Romero, Carla, Antonio Doménech Carbó, Milagros Buendía Ortuño, Trinidad Pasíes Oviedo, and María Teresa Doménech Carbó. "Aportación de nuevas metodologías multitécnica en el estudio y conservación de patrimonio numismático de procedencia subacuática." Ge-conservacion 16 (December 1, 2019): 92–105. http://dx.doi.org/10.37558/gec.v16i0.685.

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Este trabajo presenta un estudio del estado de conservación de monedas con base de cobre procedente del Museo Nacional de Arqueología Subacuática. La metodología multitécnica incluye instrumentación convencional como microscopía óptica, espectroscopia FTIR y técnicas avanzadas nanoinvasivas como voltamperometría de micropartículas y haz de iones focalizados-FESEM-EDX. Así se ha podido identificar el tipo de aleación, productos de corrosión, depósitos superficiales y antiguas intervenciones. Cabe señalar la identificación de mecanismos de alteración atípicos como la formación de complejos carboxilados de iones metálicos generados en los procesos electroquímicos de corrosión del metal o aleación y los materiales lipídicos fijados en la superficie de la moneda cuando esta estuvo en circulación y que gracias a su carácter hidrófobo se han conservado en el ambiente subacuático en el que las monedas han permanecido durante siglos. Estos hallazgos han resultado de gran utilidad para establecer los tratamientos más idóneos de conservación de estas piezas.

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Muedas Taipe, Golfer, Andrea Leticia Almandoz Landa, and Fátima Amanda Santillán Espinoza. "PREPARACIÓN Y CARACTERIZACIÓN DE BIOSORBENTES BASADOS EN COMPÓSITOS DE MWCNT-MAGNETITAHIDROXIAPATITA Y SU POTENCIAL APLICACIÓN EN LA REMOCIÓN DE METALES PESADOS." Revista de la Sociedad Química del Perú 85, no. 4 (2019): 463–75. http://dx.doi.org/10.37761/rsqp.v85i4.260.

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En el presente estudio, se prepararon nuevos biosorbentes basados en compósitos de magnetita (Fe3 O4 ), hidroxiapatita (HAp) y nanotubos de carbono de pared múltiple (MWCNT). Los materiales preparados fueron caracterizados mediante técnicas de dispersión dinámica de luz (DLS) espectroscopía infrarroja (FTIR), microscopía electrónica de barrido (SEM), magnetometría de muestra vibrante (VSM), espectroscopía Raman y voltamperometría de onda cuadrada. La magnetita sintetizada presentó un comportamiento ferromagnético. La HAp tuvo menor tamaño mediante la síntesis hidrotermal. Además, se evaluó el posible uso del compósito que involucraba a los tres materiales de partida (Fe3 O4 /MWCNT/HAp) en la remoción de un metal pesado como As(V) en solución acuosa, teniendo en cuenta la influencia de factores como pH, masa de adsorbente y tiempo de contacto. Se obtuvo los valores máximos de porcentaje de remoción de este metal (mayor a 85 %) a condiciones de pH 6, dosis de adsorbente de 0,5 g L-1 y un tiempo de contacto de 2 h.

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Solarte Ordóñez, Maricela, and Edier Humberto Perez. "DETERMINACIÓN DE COBRE UNIDO A LA FRACCIÓN DE ÁCIDOS FÚLVICOS DE UN SUELO ANDISOL DEL CAUCA MEDIANTE VOLTAMPEROMETRÍA." Suelos Ecuatoriales 50, no. 1y2 (2020): 26–30. http://dx.doi.org/10.47864/se(50)2020p26-30_115.

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Se evaluó el Cu2+ unido a la fracción de ácidos fúlvicos mediante voltamperometría encontrándose que el 1% del Cu2+ total se encuentra unido a dicha fracción, indicando un riesgo potencial para la contaminación ambiental, debido a su alta solubilidad en todo el rango de pH. Para su estudio se aislaron las fracciones de humus de un suelo Andisol del Departamento del Cauca, su fracción de ácidos fúlvicos fue extraída mediante método granulométrico y extracciones sucesivas con soluciones básicas. Su purificación se realizó a través de resinas de adsorción amberlita XAD-16, de intercambio Rexyn101-H y membranas de diálisis. Se caracterizó mediante técnicas espectroscópicas, relación E4/E6, acidez total y cromatografía de exclusión molecular a través de sephadex G-75.  Los grupos carboxílicos fueron la fracción ionizable predominante en comparación con los grupos fenólicos y alcohólicos. Se obtuvo dos fracciones a través del sephadex: una correspondiente a moléculas con peso molecular superior a 50000 daltons y otra que comprende moléculas con tamaño molecular en un rango de 1000 a 50000 daltons.

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Marquez, Ricardo, and Luis Humberto Mendoza Huizar. "A Voltamperometric Study of the Platinum Electrodeposition on Glassy Carbon Electrode. Influence of the Temperature of the Plating Bath." ECS Transactions 94, no. 1 (2019): 339–43. http://dx.doi.org/10.1149/09401.0339ecst.

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Rendón Enríquez, Ibeth, and Julio César Aguilar Cordero. "Estudio Electroquímico de Monocapas Autoensambladas de Cisteamina Funcionalizadas con 6-metil-2-piridincarboxaldehído." Química Central 2, no. 1 (2011): 33–38. http://dx.doi.org/10.29166/quimica.v2i1.548.

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En este trabajo se presenta un estudio sistemático de la formación de una Monocapa Autoensamblada (MAE) de Cisteamina (CA) sobre electrodos de oro. Esta monocapa fue funcionalizada con 6-metil-2-piridincarboxaldehído (MPC) mediante la formación de una base de Schiff capaz de fijar iones metálicos a fin de cuantificarlos en solución acuosa. Para analizar las propiedades electroquímicas de las superficies de oro modificadas en presencia de un mediador redox se realizaron estudios de Voltamperometría Cíclica (VC) y Espectroscopía Electroquímica de Impedancia (EIS). La respuesta de esta modificación depende de la interacción con el analito (CA, MPC o ión metálico) pero también se tomaron en cuenta las interacciones del medio acuoso de fosfatos(solución amortiguadora) en el que se llevó a cabo los estudios. Mediante dicho estudio se pudo determinar si la monocapa utilizada es apta para ser empleada como un sensor impedimétrico, llegando a establecerse que la base de Schiff no logra estabilizarse en la solución de fosfatos por lo que no es posible utilizar dicho electrodo modificado como un sensor impedimétrico.

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Villada, Juan D., Juliana Loaiza, and Manuel N. Chaur. "Electronic and electrochemical properties of a grid-like structure of Zn(II)." Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales 43, no. 167 (2019): 273. http://dx.doi.org/10.18257/raccefyn.822.

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Una nueva bis(hidrazona), altamente soluble en solventes orgánicos comunes, se sintetizó y caracterizó mediante diversas técnicas espectroscópicas. El compuesto se utilizó como ligando ditópico en la construcción de estructuras supramoleculares de tipo rejilla (rejillas supramoleculares o complejos metálicos de tipo rejilla) utilizando Zn2+ como catión metálico. El complejo supramolecular se confirmó mediante resonancia magnética nuclear RMN-1H y bidimensional. El arreglo de tipo rejilla se determinó mediante las señales de RMN-1H del anillo fenilo del ligando orgánico que cambia su velocidad de rotación y, por ende, su ambiente químico al coordinarse en dicho arreglo. Por último, se realizaron estudios de UV-Vis y voltamperometría cíclica y de onda cuadrada, con el fin de determinar las propiedades optoelectrónicas y electroquímicas de estos compuestos. Tanto la bis(hidrazona) como el complejo de tipo rejilla aquí presentados, exhiben varios potenciales de oxidación-reducción, los cuales se estudiaron en detalle mediante las técnicas mencionadas y cuyo estudio sirve de base para el desarrollo futuro de estructuras supramoleculares que puedan utilizarse como interruptores moleculares electroquímicos. © 2019. Acad. Colomb. Cienc. Ex. Fis. Nat.

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Journal articles on the topic 'VOLTAMPEROMETRY'

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