Journal articles: 'Electrodes positives'

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Straka, Malgorzata, Benjamin Shafer, Srikanth Vasudevan, Cristin Welle, and Loren Rieth. "Characterizing Longitudinal Changes in the Impedance Spectra of In-Vivo Peripheral Nerve Electrodes." Micromachines 9, no. 11 (November 12, 2018): 587. http://dx.doi.org/10.3390/mi9110587.

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Characterizing the aging processes of electrodes in vivo is essential in order to elucidate the changes of the electrode–tissue interface and the device. However, commonly used impedance measurements at 1 kHz are insufficient for determining electrode viability, with measurements being prone to false positives. We implanted cohorts of five iridium oxide (IrOx) and six platinum (Pt) Utah arrays into the sciatic nerve of rats, and collected the electrochemical impedance spectroscopy (EIS) up to 12 weeks or until array failure. We developed a method to classify the shapes of the magnitude and phase spectra, and correlated the classifications to circuit models and electrochemical processes at the interface likely responsible. We found categories of EIS characteristic of iridium oxide tip metallization, platinum tip metallization, tip metal degradation, encapsulation degradation, and wire breakage in the lead. We also fitted the impedance spectra as features to a fine-Gaussian support vector machine (SVM) algorithm for both IrOx and Pt tipped arrays, with a prediction accuracy for categories of 95% and 99%, respectively. Together, this suggests that these simple and computationally efficient algorithms are sufficient to explain the majority of variance across a wide range of EIS data describing Utah arrays. These categories were assessed over time, providing insights into the degradation and failure mechanisms for both the electrode–tissue interface and wire bundle. Methods developed in this study will allow for a better understanding of how EIS can characterize the physical changes to electrodes in vivo.

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Martins, Beatriz R., Yanne O. Barbosa, Cristhianne M. R. Andrade, Loren Q. Pereira, Guilherme F. Simão, Carlo J. de Oliveira, Dalmo Correia, et al. "Development of an Electrochemical Immunosensor for Specific Detection of Visceral Leishmaniasis Using Gold-Modified Screen-Printed Carbon Electrodes." Biosensors 10, no. 8 (July 23, 2020): 81. http://dx.doi.org/10.3390/bios10080081.

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Visceral leishmaniasis is a reemerging neglected tropical disease with limitations for its diagnosis, including low concentration of antibodies in the serum of asymptomatic patients and cross-reactions. In this context, this work proposes an electrochemical immunosensor for the diagnosis of visceral leishmaniasis in a more sensitive way that is capable of avoiding cross-reaction with Chagas disease (CD). Crude Leishmania infantum antigens tested in the enzyme-linked immunosorbent assay (ELISA) were methodologically standardized to best engage to the sensor. The antibodies anti-Trypanosoma cruzi and anti-Leishmania sp. Present in serum from patients with diverse types of CD or leishmaniasis were chosen. A screen-printed carbon electrode modified with gold nanoparticles was the best platform to guarantee effective adsorption of all antigens so that the epitope of specific recognition for leishmaniasis occurred efficiently and without cross-reaction with the evaluated CD. The current peaks reduced linearly after the recognition, and still were able to notice the discrimination between different kinds of diseases (digestive, cardiac, undetermined Chagas/acute and visceral chronic leishmaniasis). Comparative analyses with ELISA were performed with the same groups, and a low specificity (44%) was verified due to cross-reactions (high number of false positives) on ELISA tests, while the proposed immunosensor presented high selectivity and specificity (100%) without any false positives or false negatives for the serum samples from isolated patients with different types of CD and visceral leishmaniasis. Furthermore, the biosensor was stable for 5 days and presented a detection limit of 200 ng mL−1.

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Elvira, María, Eduardo Iáñez, Vicente Quiles, Mario Ortiz, and José M. Azorín. "Pseudo-Online BMI Based on EEG to Detect the Appearance of Sudden Obstacles during Walking." Sensors 19, no. 24 (December 10, 2019): 5444. http://dx.doi.org/10.3390/s19245444.

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The aim of this paper is to describe new methods for detecting the appearance of unexpected obstacles during normal gait from EEG signals, improving the accuracy and reducing the false positive rate obtained in previous studies. This way, an exoskeleton for rehabilitation or assistance of people with motor limitations commanded by a Brain-Machine Interface (BMI) could be stopped in case that an obstacle suddenly appears during walking. The EEG data of nine healthy subjects were collected during their normal gait while an obstacle appearance was simulated by the projection of a laser line in a random pattern. Different approaches were considered for selecting the parameters of the BMI: subsets of electrodes, time windows and classifier probabilities, which were based on a linear discriminant analysis (LDA). The pseudo-online results of the BMI for detecting the appearance of obstacles, with an average percentage of 63.9% of accuracy and 2.6 false positives per minute, showed a significant improvement over previous studies.

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Tsai, Shan-Ho, Ying-Ru Chen, Yi-Lin Tsou, Tseng-Lung Chang, Hong-Zheng Lai, and Chi-Young Lee. "Applications of Long-Length Carbon Nano-Tube (L-CNT) as Conductive Materials in High Energy Density Pouch Type Lithium Ion Batteries." Polymers 12, no. 7 (June 30, 2020): 1471. http://dx.doi.org/10.3390/polym12071471.

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Lots of lithium ion battery (LIB) products contain lithium metal oxide LiNi5Co2Mn3O2 (LNCM) as the positive electrode’s active material. The stable surface of this oxide results in high resistivity in the battery. For this reason, conductive carbon-based materials, including acetylene black and carbon black, become necessary components in electrodes. Recently, carbon nano-tube (CNT) has appeared as a popular choice for the conductive carbon in LIB. However, a large quantity of the conductive carbon, which cannot provide capacity as the active material, will decrease the energy density of batteries. The ultra-high cost of CNT, compared to conventional carbon black, is also a problem. In this work, we are going to introduce long-length carbon nano-tube s(L-CNT) into electrodes in order to design a reduced-amount conductive carbon electrode. The whole experiment will be done in a 1Ah commercial type pouch LIB. By decreasing conductive carbon as well as increasing the active material in the positive electrode, the energy density of the LNCM-based 1Ah pouch type LIB, with only 0.16% of L-CNT inside the LNCM positive electrode, could reach 224 Wh/kg and 549 Wh/L, in weight and volume energy density, respectively. Further, this high energy density LIB with L-CNT offers stable cyclability, which may constitute valuable progress in portable devices and electric vehicle (EV) applications.

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Mittmann, Philipp, Ingo Todt, Arneborg Ernst, Grit Rademacher, Sven Mutze, Sophia Göricke, Marc Schlamann, Stephan Lang, Diana Arweiler-Harbeck, and Florian Christov. "Radiological and NRT-Ratio–Based Estimation of Slim Straight Cochlear Implant Electrode Positions." Annals of Otology, Rhinology & Laryngology 126, no. 1 (October 25, 2016): 73–78. http://dx.doi.org/10.1177/0003489416675355.

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Objectives: An intraoperative neural response telemetry-ratio (NRT-ratio) was established, which can provide information about the intraoperative intracochlear electrode array position for perimodiolar electrodes. Methods: In a retrospective controlled study in 2 tertiary referral centers, the electrophysiological data sets of 50 patients with measured intraoperative auto-NRTs and postoperative radiological examinations were evaluated. All patients were implanted with Nucleus slim straight electrodes. The NRT-ratio was calculated by dividing the average auto-NRT data from electrodes 16 to 18 with the average from electrodes 5 to 7. Using a flat panel tomography system or a computed tomography, the position of the electrode array was certified radiological. Results: Radiologically, 2 out of 50 patients were identified with an electrode translocated from the scala tympani into the scala vestibuli. The radiologically estimated electrodes indicating a scalar change showed a regular NRT-ratio but nonspecific NRT-level changes at the localization of translocation.

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Santos, V. E. O., V. G. Celante, M. F. F. Lelis, and M. B. J. G. Freitas. "Chemical and electrochemical recycling of the nickel, cobalt, zinc and manganese from the positives electrodes of spent Ni–MH batteries from mobile phones." Journal of Power Sources 218 (November 2012): 435–44. http://dx.doi.org/10.1016/j.jpowsour.2012.07.024.

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Wu, Jian Bo, Yong Feng Yuan, and Wei Ping Chen. "CNT-CoO Complex Conductive Agent for the Positive Electrodes of MH/Ni Batteries." Materials Science Forum 610-613 (January 2009): 488–91. http://dx.doi.org/10.4028/www.scientific.net/msf.610-613.488.

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CoO was usually added to the positive electrodes of MH/Ni batteries as the conductive agent. In this paper, well crystallized multi-walled carbon nanotubes (CNTs) with diameter about 10 nm were added to the positive electrodes of MH/Ni batteries together with CoO. During the process of transformation from CoO to CoOOH, a complex conductive network was created with CNTs as the frame. Because of the high conductivity and the excellent tension characteristics of CNTs, the charge-transfer capability of the electrode was improved and the integrality of the complex conductive network was enhanced. The electrochemical measurements indicated that the impedance of the electrode with CNT-CoO complex conductive agent was lessened compared to the electrode with simple CoO agent. Performance tests of the sealed batteries showed that the positive electrodes with CNT-CoO complex conductive agent exhibited higher discharge voltage, improved capacity, modified discharge stability and prolonged lifespan, especially at high current rates.

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Zheng, H. Z., Y. J. Zhu, Z. J. Zhang, X. R. Lin, Z. J. Zhou, X. C. Ye, and S. G. Wu. "The Effect of Electrodes’ Making Methods on the Electrochemical Performance of Nano-Ni(OH)₂." Applied Mechanics and Materials 79 (July 2011): 123–27. http://dx.doi.org/10.4028/www.scientific.net/amm.79.123.

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Nano-Ni(OH)2 doped with special elements were prepared by supersonic co-precipitation method. Complex electrodes were prepared by immersion method and handwork method by mixing 8wt.% nickel hydroxides with commercial micro-size spherical nickel as the positive material of Ni-MH battery. The electrochemical performance and cyclic character affected by different electrodes’ making methods were characterized in this article. The result indicates that the discharge capacities of IM electrodes (IM electrodes mean electrodes made by handwork method) are higher than that of HM electrodes (HM electrodes mean electrodes made by handwork method). Furthermore, IM electrodes have better reversibility and higher charge efficiency than HM electrode, and lower charge potential and higher discharge plateau were also observed for IM electrodes. It's worth noting that the phenomenon is more obvious at high charge/discharge rate. When the discharge rate is 0.5C，the discharge capacity of IM electrode is higher 67.1 mAh•g -1 than that of HM electrode.

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Eliseeva, Svetlana N., Mikhail A. Kamenskii, Elena G. Tolstopyatova, and Veniamin V. Kondratiev. "Effect of Combined Conductive Polymer Binder on the Electrochemical Performance of Electrode Materials for Lithium-Ion Batteries." Energies 13, no. 9 (May 1, 2020): 2163. http://dx.doi.org/10.3390/en13092163.

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The electrodes of lithium-ion batteries (LIBs) are multicomponent systems and their electrochemical properties are influenced by each component, therefore the composition of electrodes should be properly balanced. At the beginning of lithium-ion battery research, most attention was paid to the nature, size, and morphology peculiarities of inorganic active components as the main components which determine the functional properties of electrode materials. Over the past decade, considerable attention has been paid to development of new binders, as the binders have shown great effect on the electrochemical performance of electrodes in LIBs. The study of new conductive binders, in particular water-based binders with enhanced electronic and ionic conductivity, has become a trend in the development of new electrode materials, especially the conversion/alloying-type anodes. This mini-review provides a summary on the progress of current research of the effects of binders on the electrochemical properties of intercalation electrodes, with particular attention to the mechanisms of binder effects. The comparative analysis of effects of three different binders (PEDOT:PSS/CMC, CMC, and PVDF) for a number of oxide-based and phosphate-based positive and negative electrodes for lithium-ion batteries was performed based on literature and our own published research data. It reveals that the combined PEDOT:PSS/CMC binder can be considered as a versatile component of lithium-ion battery electrode materials (for both positive and negative electrodes), effective in the wide range of electrode potentials.

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Lim, Jong-Min, and Chung-Seog Choi. "Study on the Analysis of Restrike Pattern and Radial Spectrum of AC Arc Discharge based on the Electrode Material." Fire Science and Engineering 35, no. 4 (August 31, 2021): 58–64. http://dx.doi.org/10.7731/kifse.2c23dfaa.

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In this study, we designed and fabricated a system based on IEC-62606 and UL-1699 such that stable arc discharge could be produced. AC arc discharge was performed to interpret the restrike pattern and radiation spectrum according to the electrode material. In the voltage waveform analysis of flat copper electrodes, it was analyzed that the accompaniment cycle of the negative waveform was more unstable than the half cycle of the positive waveform. We observed that the radiation spectrum of copper electrodes occurred in the ultraviolet and visible light regions. Moreover, the voltage waveform of the carbon electrode was found to be similar to the pattern produced by the copper electrode. However, we observed that the restrike generated at the half cycle of the negative waveform was produced relatively faster. The radio spectra were strongest near 589 nm, 671 nm, and 766 nm. AC arc discharges using copper electrodes and carbon electrodes were found to be between the arc-discharge patterns of copper electrodes and carbon electrodes. It has been proven that depending on the material of the electrode, there are differences in voltage list like, current patterns, and radiated spectra bands.

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11

Nam, Young Jin, Kern Ho Park, Dae Yang Oh, Woo Hyun An, and Yoon Seok Jung. "Diagnosis of failure modes for all-solid-state Li-ion batteries enabled by three-electrode cells." Journal of Materials Chemistry A 6, no. 30 (2018): 14867–75. http://dx.doi.org/10.1039/c8ta03450h.

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12

Watanabe, Toshio, Yohei Yamada, Haruhiko Sakuraba, Mikito Yasuzawa, Toshio Takayanagi, and Tomoki Yabutani. "The Hydrophobic Effect on Electrodeposition of Billirubin Oxidase CotA." Advanced Materials Research 1110 (June 2015): 291–94. http://dx.doi.org/10.4028/www.scientific.net/amr.1110.291.

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The hydrophobic effect on electrodeposition of an enzyme CotA was investigated. The CotA was electrodeposited on a gold disc electrode modified with an alkane thiol self-assembled monolayer (SAM). The CotA immobilized hydrophobic SAM gold electrodes exhibited a larger electrochemical activity compared with the hydrophilic SAM and bare electrodes. In particular, large current responses were observed in an ethanethiol or a 1-butanethiol SAM gold electrode. In addition, effect of addition of non-ionic surfactant Triton X on the electrodeposition was checked using the SAM gold electrode. The addition of Triton X had a positive effect on the electrodeposition.

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Ratynski, Maciej, Bartosz Hamankiewicz, Michal Krajewski, Maciej Boczar, Dominika Ziolkowska, and Andrzej Czerwinski. "Single Step, Electrochemical Preparation of Copper-Based Positive Electrode for Lithium Primary Cells." Materials 11, no. 11 (October 29, 2018): 2126. http://dx.doi.org/10.3390/ma11112126.

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Lithium primary cells are commonly used in applications where high energy density and low self-discharge are the most important factors. This include small coin cells for electronics, power backup batteries for complementary metal-oxide-semiconductor memory or as a long-term emergency power source. In our study we present a fast, electrochemical method of the positive electrode preparation for lithium primary cells. The influence of the current density and oxygen presence in a solution on the preparation of the electrode and thus its electrochemical behavior is examined. Electrode compositions were characterized by X-ray photoelectron spectroscopy (XPS). The prepared electrodes may be used in Li cells as competition to Zn-MnO2 primary batteries.

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Rocha Neto, João Batista Maia, Andrey Coatrini Soares, Rogério Aparecido Bataglioli, Olívia Carr, Carlos Alberto Rodrigues Costa, Osvaldo N. Oliveira, Marisa Masumi Beppu, and Hernandes F. Carvalho. "Polysaccharide Multilayer Films in Sensors for Detecting Prostate Tumor Cells Based on Hyaluronan-CD44 Interactions." Cells 9, no. 6 (June 26, 2020): 1563. http://dx.doi.org/10.3390/cells9061563.

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The increasing need for point-of-care diagnosis has sparked the development of label-free sensing platforms, some of which are based on impedance measurements with biological cells. Here, interdigitated electrodes were functionalized with layer-by-layer (LbL) films of hyaluronan (HA) and chitosan (CHI) to detect prostatic tumor cells (PC3 line). The deposition of LbL films was confirmed with atomic force microscopy and polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS), which featured the vibrational modes of the HA top layer capable of interacting specifically with glycoprotein CD44 receptors overexpressed in tumor cells. Though the CHI/HA LbL films cannot be considered as a traditional biosensor due to their limited selectivity, it was possible to distinguish prostate tumor cells in the range from 50 to 600 cells/µL in in vitro experiments with impedance spectroscopy. This was achieved by treating the impedance data with information visualization methods, which confirmed the distinguishing ability of the films by observing the absence of false positives in a series of control experiments. The CD44–HA interactions may, therefore, be exploited in clinical analyses and point-of-care diagnostics for cancer, particularly if computational methods are used to process the data.

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Buckley, D. N., A. Bourke, R. P. Lynch, N. Quill, M. A. Miller, J. S. Wainright, and R. F. Savinell. "Influence of Pretreatment on Kinetics at Carbon Electrodes and Consequences for Flow Battery Performance." MRS Advances 2, no. 21-22 (2017): 1131–42. http://dx.doi.org/10.1557/adv.2017.176.

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ABSTRACTUsing cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), it was shown for four different types of carbon that electrode treatments at negative potentials enhance the kinetics of VIV-VV and inhibit the kinetics of VII-VIII while electrode treatments at positive potentials inhibit the kinetics of VIV-VV and enhance the kinetics of VII-VIII. These observations may explain conflicting reports in the literature. The potentials required for activation and deactivation of electrodes were examined in detail. The results suggest that interchanging the positive and negative electrodes in a vanadium flow battery (VFB) would reduce the overpotential at the negative electrode and so improve the performance. This is supported by flow-cell experiments. Thus, periodic catholyte-anolyte interchange, or equivalent alternatives such as battery overdischarge, show promise of improving the voltage efficiency of VFBs.

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Brolo, A. G., and D. E. Irish. "SERS studies of monoprotonated pyrazine (pyrazinium) cations adsorbed onto positively charged silver electrodes." Canadian Journal of Chemistry 75, no. 11 (November 1, 1997): 1643–48. http://dx.doi.org/10.1139/v97-195.

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The surface-enhanced Raman scattering (SERS) spectra of monoprotonated pyrazine cations adsorbed on silver electrodes have been measured. The molecular orientation of the pyrazinium cation is dependent on the electrode potential. At potentials more positive than −170 mV the monoprotonated pyrazine is adsorbed end-on. However, the spectral features suggest a flat orientation as the potential becomes more negative than −300 mV. Monoprotonated pyrazine cations with both orientations can coexist at potentials between these limits. The adsorption of the positive ion to a positively charged electrode is mediated by specifically adsorbed bromide ions. Keywords: SERS; monoprotonated pyrazine cation, silver electrode, pyrazinium.

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Housel, Lisa M., Alyson Abraham, Genesis D. Renderos, Kenneth J. Takeuchi, Esther S. Takeuchi, and Amy C. Marschilok. "Surface Electrolyte Interphase Control on Magnetite, Fe3O4, Electrodes: Impact on Electrochemistry." MRS Advances 3, no. 11 (2018): 581–86. http://dx.doi.org/10.1557/adv.2018.294.

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ABSTRACTIn battery systems, a solid electrolyte interphase (SEI) is formed through electrolyte reaction on an electrode surface. The formation of SEI can have both positive and negative effects on electrochemistry. The initial formation of the layer protects the electrode from further reactivity, which can improve both shelf and cycle life. However, if the layer continues to form, it can impede charge transfer, which increases cell resistance and limits cycle life. The role of SEI is particularly important when studying conversion electrodes, since phase transformations which unveil new electroactive surfaces during reduction/oxidation can facilitate electrolyte decomposition. This manuscript highlights recent developments in the understanding and control of SEI formation for magnetite (Fe3O4) conversion electrodes through electrolyte and electrode modification.

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Ghosh, Souvik, Aparna Paul, Prakas Samanta, Bhau Landge, Sanjib Kumar Mandal, Sangam Sinha, Gour Gopal Dutta, Naresh Chandra Murmu, and Tapas Kuila. "Influence of Transition Metals (Cu and Co) on the Carbon-Coated Nickel Sulfide Used as Positive Electrode Material in Hybrid Supercapacitor Device." Journal of Composites Science 5, no. 7 (July 8, 2021): 180. http://dx.doi.org/10.3390/jcs5070180.

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Herein, a facile, environment-friendly and cost-effective approach was followed for the preparation of metal sulfide-based supercapacitor electrodes. The effect of transition metal interrogation on the morphology and electrochemical performance of carbon-coated nickel sulfide composite electrode was investigated. Physicochemical characterization showed that the enhancement in electrical conductivity and electrochemical reaction sites with the introduction of copper (Cu) and cobalt (Co) was due to the variation in morphology. Fast ionic transformation and improvement in the number of redox active sites might improve the supercapacitor performance. The electrochemical experiment showed that the NCoSC electrode exhibited the highest capacitance value of ~760 F g−1 at 2 A g−1 current density as compared to the NCuSC and NSC electrodes. Therefore, a hybrid supercapacitor (HSC) device was fabricated by using NCoSC as the positive electrode and thermally reduced graphene oxide (TRGO) as the negative electrode. The fabricated device demonstrated maximum energy density of ~38.8 Wh Kg−1 and power density of 9.8 kW Kg−1. The HSC device also showed ~89.5% retention in specific capacitance after 10,000 charge–discharge cycles at 12 A g−1 current density. So, the tuning of electronic and physical properties by the introduction of Cu and Co on nickel sulfide improved the supercapacitor performance.

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Angel, S. M., L. F. Katz, D. D. Archibald, L. T. Lin, and D. E. Honigs. "Near-Infrared Surface-Enhanced Raman Spectroscopy. Part I: Copper and Gold Electrodes." Applied Spectroscopy 42, no. 8 (November 1988): 1327–31. http://dx.doi.org/10.1366/0003702884429698.

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Surface-enhanced Raman spectra of pyridine on copper and gold electrodes in the near-infrared were obtained with a Fourier transform Raman spectrometer. Surface-enhanced Raman spectra were observed for pyridine adsorbed on copper and gold electrodes while a Nd:YAG laser (1.064/μm) was used for excitation. Good-quality spectra were recorded for 0.08 mM pyridine on a copper electrode with a single oxidation-reduction cycle, whereas for a gold electrode, several ORCs were necessary. A very intense low-energy Raman band was observed on both metals at positive potentials, which may be due to a metal-oxide vibrational mode.

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Kuang, Peijing, Yubo Cui, Chuanping Feng, and Yasuaki Einaga. "Study of nitrate contaminants removal from groundwater on copper modified BDD electrode." E3S Web of Conferences 194 (2020): 04024. http://dx.doi.org/10.1051/e3sconf/202019404024.

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The electrochemical nitrate reduction by using boron-doped diamond (BDD) and copper modified boron-doped diamond (Cu-BDD) electrodes was investigated at various potentials. Nitrate reduction efficiency and the products distribution was strongly dependent on the applied potential for both electrodes. The highest nitrate reduction efficiency of 77% was obtained at −2.0 V (vs. Ag/AgCl) by using Cu-BDD. Compared with BDD electrode, nitrate reduction on Cu-BDD electrode occurred at more positive potential. Copper oxides formed on BDD surface efficiently promoted enhanced conductivity of electrode to promote electrons transfer during nitrate reduction process. Meanwhile, the catalytic ability of copper was also conductive to the nitrate transformation. Therefore, the developed Cu-BDD would be a promising approach for efficient nitrate removal from groundwater.

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Varzi, Alberto, Corina Täubert, Margret Wohlfahrt-Mehrens, Martin Kreis, and Walter Schütz. "Study of Carbon Nanotubes for Lithium-Ion Batteries Application." Advances in Science and Technology 72 (October 2010): 299–304. http://dx.doi.org/10.4028/www.scientific.net/ast.72.299.

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The potential use of multi-walled carbon nanotubes (MWCNTs) produced by chemical vapour deposition (CVD) as a conductive agent for electrodes in Li-ion batteries has been investigated. LiNi0.33Co0.33Mn0.33O2 (NCM) has been chosen as active material for positive electrodes, and a nano-sized TiO2-rutile for the negative electrodes. The electrochemical performances of the electrodes were studied by galvanostatic techniques and especially the influence of the nanotubes on the rate capability and cycling stability has been evaluated. The addition of MWCNTs significantly enhanced the rate performances of both positive and negative electrodes and improved the capacity retention upon cycling. The obtained results demonstrated that the addition of MWCNTs in low amounts to the electrode composition enables an increase in both energy and power density of a Li-ion battery.

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Liu, Yu, Wen Chao Zhang, Sheng Fang Zhang, and Zhi Hua Sha. "The Simulation Research of Tool Wear in Small Hole EDM Machining on Titanium Alloy." Applied Mechanics and Materials 624 (August 2014): 249–54. http://dx.doi.org/10.4028/www.scientific.net/amm.624.249.

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This article has carried on the simulation research of tool wear in electrical discharge machining (EDM) small holes on titanium alloy with the finite element method. Aiming at electrode material removal process in EDM, a 3D thermodynamics model of single pulse discharge material removal is established with Ansys software. By simulating the Gaussian distribution of heat flux and thermal convection loads of discharge channel, the same type of surface heat source is exerted on both positive and negative electrodes with different distribution coefficients and different material characteristics, to analyze the surface temperature field in the region of tool and workpiece processing area, and respectively obtain the heat distribution law along the radius and depth directions of copper and titanium alloy electrodes, in the condition of small hole positive polarity EDM machining on TC4 with copper as the tool electrode. Using the birth and death element method, the volumes of material removal on both electrodes are calculated to analyze the tool wear. The experiments of small hole EDM machining on TC4 are carried out, and the results of simulation and experiment are compared. It is shown that the simulation model can not only accurately predict the relative wear of both electrodes, the simulation results of material removal volumes on both electrodes are also almost accurate.

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Takeuchi, Akihiro, Kan Okubo, and Nobunao Takeuchi. "Electric Signals on and under the Ground Surface Induced by Seismic Waves." International Journal of Geophysics 2012 (2012): 1–10. http://dx.doi.org/10.1155/2012/270809.

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We constructed three observation sites in northeastern Japan (Honjo, Kyowa, and Sennan) with condenser-type large plate electrodes (4 × 4 m2) as sensors supported 4 m above the ground and with pairs of reference electrodes buried vertically at 0.5 m and 2.5 m depth (with a ground velocity sensor at Sennan only). Electrical signals of an earthquake (M6.3) in northeastern Japan were detected simultaneously with seismic waves. Their waveforms were damped oscillations, with greatly differing signal amplitudes among sites. Good positive correlation was found between the amplitudes of signals detected by all electrodes. We propose a signal generation model: seismic acceleration vertically shook pore water in the topsoil, generating the vertical streaming potential between the upper unsaturated water zone and the lower saturated water zone. Maximum electric earth potential difference was observed when one electrode was in the saturated water zone, and the other was within the unsaturated water zone, but not when the electrodes were in the saturated water zone. The streaming potential formed a charge on the ground surface, generating a vertical atmospheric electric field. The large plate electrode detected electric signals related to electric potential differences between the electrode and the ground surface.

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Pan, Yusheng, Ke Xu, and Canliu Wu. "Recent progress in supercapacitors based on the advanced carbon electrodes." Nanotechnology Reviews 8, no. 1 (November 26, 2019): 299–314. http://dx.doi.org/10.1515/ntrev-2019-0029.

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Abstract This paper demonstrates a brief review of the research progress of the advanced carbon-based materials for the supercapacitor electrodes. Diverse types of carbon-based electrodes exploited and reported to the literature are summarized and classified into pure carbon electrodes, carbon/metal oxides composite electrodes, carbon/metal oxides/conducting polymers composite electrodes as well as carbon electrodes based on other materials. Pure carbon electrodes are firstly introduced, confirming their merits and shortcomings. To cover the shortage of pure carbon electrodes and further enhances their electrochemical performance, a composite electrode, combined with metal oxides and conducting polymers, is respectively presented. It is worth noticing in this article that combining various materials to form composites has been one main direction to own a positive synergistic effect on the carbon-based electrodes.

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Finucane, Kevin E., Janine A. Panizza, and Bhajan Singh. "Efficiency of the normal human diaphragm with hyperinflation." Journal of Applied Physiology 99, no. 4 (October 2005): 1402–11. http://dx.doi.org/10.1152/japplphysiol.01165.2004.

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We evaluated an index of diaphragm efficiency (Effdi), diaphragm power output (Ẇdi) relative to electrical activation, in five healthy adults during tidal breathing at usual end-expiratory lung volume (EELV) and diaphragm length ( Ldi ee) and at shorter Ldi ee during hyperinflation with expiratory positive airway pressure (EPAP). Measurements were repeated with an inspiratory threshold (7.5 cmH2O) plus resistive (6.5 cmH2O·l−1·s) load. Ẇdi was the product of mean inspiratory transdiaphragmatic pressure (ΔPdimean), diaphragm volume displacement measured fluoroscopically, and 1/inspiratory duration (Ti−1). Diaphragm activation, measured with esophageal electrodes, was quantified by computing root-mean-square values (RMSdi). With EPAP, 1) EELV increased [mean r2 = 0.91 (SD 0.01)]; 2) in four subjects, Ldi ee decreased [mean r2 = 0.85 (SD 0.07)] and mean Effdi decreased 34% per 10% decrease in Ldi ee ( P < 0.001); and 3) in one subject, gastric pressure at EELV increased two- to threefold, Ldi ee was unchanged or increased, and Effdi increased at two of four levels of EPAP ( P ≤ 0.006, ANOVA). Inspiratory loading increased Ẇdi ( P = 0.003) and RMSdi ( P = 0.004) with no change in Effdi ( P = 0.63) or its relationship with Ldi ee. Effdi was more accurate in defining changes in Ldi ee [(true positives + true negatives)/total = 0.78 (SD 0.13)] than ΔPdimean·RMSdi−1, RMSdi, or ΔPdimean·Ti (all <0.7, P ≤ 0.05, without load). Thus Effdi was principally a function of Ldi ee independent of inspiratory loading, behavior consistent with muscle force-length-velocity properties. We conclude that Effdi, measured during tidal breathing and in the absence of expiratory muscle activity at EELV, is a valid and accurate measure of diaphragm contractile function.

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Joo, Hwajoo, Jaehan Lee, and Jeyong Yoon. "Short Review: Timeline of the Electrochemical Lithium Recovery System Using the Spinel LiMn2O4 as a Positive Electrode." Energies 13, no. 23 (November 26, 2020): 6235. http://dx.doi.org/10.3390/en13236235.

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Various lithium recovery technologies have been developed as securing lithium resources has become increasingly important. Among these technologies, the electrochemical lithium recovery (ELR) system is a rapid and eco-friendly extraction method that has been studied recently. In this paper, an ELR system using a spinel-type LiMn2O4 (LMO) is briefly reviewed. As LMO electrodes have high Li+ selectivity and stability compared to other lithium battery cathodes, they have been widely used as positive electrodes for the ELR system. This paper summarizes the system proposal, LMO electrode modification, system analysis, and industrial applications. Perspectives of the ELR technology are presented considering the progress of the research.

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Birhane, Y. T., S. C. Lin, and F. C. Lai. "Effect of Electrode Length on the Performance of EHD Gas Pump." Applied Mechanics and Materials 598 (July 2014): 355–60. http://dx.doi.org/10.4028/www.scientific.net/amm.598.355.

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The effects of electrode length on the characteristics of flow induced by an electrohydrodynamic (EHD) gas pump in circular pipe have been experimentally examined in this study. The gas pump has a diameter of 61.8 mm and uses eight evenly spaced emitting electrodes which are flush mounted on the tube inner wall. The gap distance between emitting and ground electrodes is fixed at 25 mm and two emitting electrode lengths (15 mm and 40 mm) are considered. Experiments are conducted using positive corona discharge with voltage varying from 17.5 kV to 23 kV. Several important implications from the present results for practical engineering applications are presented.

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Pfleging, Wilhelm. "A review of laser electrode processing for development and manufacturing of lithium-ion batteries." Nanophotonics 7, no. 3 (February 23, 2018): 549–73. http://dx.doi.org/10.1515/nanoph-2017-0044.

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AbstractLaser processes for cutting, annealing, structuring, and printing of battery materials have a great potential in order to minimize the fabrication costs and to increase the electrochemical performance and operational lifetime of lithium-ion cells. Hereby, a broad range of applications can be covered such as micro-batteries, mobile applications, electric vehicles, and stand-alone electric energy storage devices. Cost-efficient nanosecond (ns)-laser cutting of electrodes was one of the first laser technologies which were successfully transferred to industrial high-energy battery production. A defined thermal impact can be useful in electrode manufacturing which was demonstrated by laser annealing of thin-film electrodes for adjusting of battery active crystalline phases or by laser-based drying of composite thick-film electrodes for high-energy batteries. Ultrafast or ns-laser direct structuring or printing of electrode materials is a rather new technical approach in order to realize three-dimensional (3D) electrode architectures. Three-dimensional electrode configurations lead to a better electrochemical performance in comparison to conventional 2D one, due to an increased active surface area, reduced mechanical tensions during electrochemical cycling, and an overall reduced cell impedance. Furthermore, it was shown that for thick-film composite electrodes an increase of electrolyte wetting could be achieved by introducing 3D micro-/nano-structures. Laser structuring can turn electrodes into superwicking. This has a positive impact regarding an increased battery lifetime and a reliable battery production. Finally, laser processes can be up-scaled in order to transfer the 3D battery concept to high-energy and high-power lithium-ion cells.

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Maskey, Anish, Atit Deuja, Suresh Basnet, and Raju Khanal. "Effect of DC Biased Voltage and Ion Temperature on Bounded Ion-Ion Plasma." Journal of Institute of Science and Technology 25, no. 1 (June 14, 2020): 61–67. http://dx.doi.org/10.3126/jist.v25i1.29449.

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A one dimensional particle-in-cell (PIC) simulation method has been employed to study the effect of DC voltage and ion temperature on the properties of ion-ion plasma bounded by two symmetrical but oppositely biased electrodes. It is assumed that the ion-ion plasma is collisionless and both the positive and negative ion species have the same mass, temperature, and degree of ionization. Simulation results show that the formation of sheath and presheath regions and fluctuation of plasma parameters in that region are affected by the biasing voltage and ion temperature. It was found that the magnitude of the electrostatic electric field at the vicinity of biasing electrodes was affected by the biasing voltage and ion temperature as well. This strong electric field close to the electrodes further prevents the flow of charged particles towards the electrodes. The presence of a non-zero electric field at the quasineutral region suggests a presheath region similar to the electron-ion plasma. In the quasineutral region, the density of ions increased with the increase in biasing voltage and decreased with the increase in temperature of isothermal ions. Furthermore, the phase space diagrams for the ions were obtained which indicated different regions of the plasma. The positive ions acquire negative velocity towards the negatively biased electrode and the negative ions acquire positive velocity towards the positively biased electrode.

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30

Hegemann, M., P. P. Bawol, A. Köllisch-Mirbach, and H. Baltruschat. "Mixed Lithium and Sodium Ion Aprotic DMSO Electrolytes for Oxygen Reduction on Au and Pt Studied by DEMS and RRDE." Electrocatalysis 12, no. 5 (May 15, 2021): 564–78. http://dx.doi.org/10.1007/s12678-021-00669-4.

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AbstractIn order to advance the development of metal-air batteries and solve possible problems, it is necessary to gain a fundamental understanding of the underlying reaction mechanisms. In this study we investigate the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER, from species formed during ORR) in Na+ containing dimethyl sulfoxide (DMSO) on poly and single crystalline Pt and Au electrodes. Using a rotating ring disk electrode (RRDE) generator collector setup and additional differential electrochemical mass spectrometry (DEMS), we investigate the ORR mechanism and product distribution. We found that the formation of adsorbed Na2O2, which inhibits further oxygen reduction, is kinetically favored on Pt overadsorption on Au. Peroxide formation occurs to a smaller extent on the single crystal electrodes of Pt than on the polycrystalline surface. Utilizing two different approaches, we were able to calculate the heterogeneous rate constants of the O2/O2− redox couple on Pt and Au and found a higher rate for Pt electrodes compared to Au. We will show that on both electrodes the first electron transfer (formation of superoxide) is the rate-determining step in the reaction mechanism. Small amounts of added Li+ in the electrolyte reduce the reversibility of the O2/O2− redox couples due to faster and more efficient blocking of the electrode by peroxide. Another effect is the positive potential shift of the peroxide formation on both electrodes. The reaction rate of the peroxide formation on the Au electrode increases when increasing the Li+ content in the electrolyte, whereas it remains unaffected on the Pt electrode. However, we can show that the mixed electrolytes promote the activity of peroxide oxidation on the Pt electrode compared to a pure Li+ electrolyte. Overall, we found that the addition of Li+ leads to a Li+-dominated mechanism (ORR onset and product distribution) as soon as the Li+ concentration exceeds the oxygen concentration. Graphical abstract

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31

Du, Tang, Li, Zou, Ma, Sun, Liu, and Zeng. "Thermal Characteristics of Positive Leaders under Different Electrode Terminals in a Long Air Gap." Energies 12, no. 21 (October 23, 2019): 4024. http://dx.doi.org/10.3390/en12214024.

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The thermal characteristics of the positive leader discharges occurring under the different electrode terminals in a 1 m rod-plate air gap were studied quantitatively using Mach–Zehnder interferometry and a high-speed video camera. When disturbed by the discharge channel, the interference fringes are distorted because of the change in the refractive index of air, which is related to the gas density. Therefore, the gas temperature and gas density distribution in the leader channel can be retrieved from the offset of the interference fringes. Based on these results, the thermal characteristics of the leader channel were studied under different electrode terminals with a radius of curvature of 2.5 mm and 5 mm for cone electrodes and a diameter of 40 mm for a spherical electrode. The results show that the gas temperature in the leader channel increased while the gas density decreased as the radius of curvature of the electrode terminal decreased. Additionally, a smaller radius of curvature leads to a larger thermal diameter, but the difference in the thermal diameter is not obvious; for the terminals used in this paper, the difference is within 2 mm.

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32

Zhang, Kai, and Bailin Zheng. "Effect of Irreversible Electrochemical Reaction on Diffusion and Diffusion-Induced Stresses in Spherical Composition–Gradient Electrodes." Zeitschrift für Naturforschung A 75, no. 1 (December 18, 2019): 55–63. http://dx.doi.org/10.1515/zna-2019-0215.

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AbstractComposition–gradient electrodes have been proved to have excellent electrochemical performances. The effect of irreversible electrochemical reaction on diffusion and diffusion-induced stresses in such electrodes is investigated. The diffusion equation and mechanical equation considering the electrochemical reaction and the heterogeneous factors are derived, and the distributions of lithium (Li) concentration and stresses in a spherical electrode are obtained under potentiostatic charging. The results indicate that the electrochemical reaction will slow down the diffusion process and enhance the stresses of the electrode. However, the heterogeneous factors of the electrochemical reaction could provide a positive effect on the stresses, which means that the heterogeneous factor is conducive to avoid capacity fading of the battery. The results suggest that the composition–gradient electrodes could be designed to have a decreasing transition form of forward reaction rate and an increasing transition form of the difference of atomic volume between reactants and the reaction product.

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33

Chang, Tzu-Chin, Yu-Hsuan Liu, Mei-Ling Chen, Chen-Chen Tseng, Yung-Sheng Lin, and Shu-Ling Huang. "Cerium/Ascorbic Acid/Iodine Active Species for Redox Flow Energy Storage Battery." Molecules 26, no. 11 (June 5, 2021): 3443. http://dx.doi.org/10.3390/molecules26113443.

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In this study, we developed a novel cerium/ascorbic acid/iodine active species to design a redox flow battery (RFB), in which the cerium nitrate hexahydrate [Ce(NO3)3·6H2O] was used as a positive Ce3+/Ce4+ ion pair, and the potassium iodate (KIO3) containing ascorbic acid was used as a negative I2/I− ion pair. In order to improve the electrochemical activity and to avoid cross-contamination of the redox pair ions, the electroless plating and sol–gel method were applied to modify the carbon paper electrode and the Nafion 117 membrane. The electrocatalytic and electrochemical properties of the composite electrode using methanesulfonic acid as a supporting electrolyte were assessed using the cyclic voltammetry (CV) test. The results showed that the Ce (III)/Ce (IV) active species presented a symmetric oxidation/reduction current ratio (1.09) on the C–TiO2–PdO composite electrode. Adding a constant amount of ascorbic acid to the iodine solution led to a good reversible oxidation/reduction reaction. Therefore, a novel Ce/ascorbic acid/I RFB was developed with C–TiO2–PdO composite electrodes and modified Nafion 117–SiO2–SO3H membrane using the staggered-type flow channel, of which the energy efficiency (EE%) can reach about 72%. The Ce/ascorbic acid/I active species can greatly reduce the electrolyte cost compared to the all-vanadium redox flow battery system, and it therefore has greater development potential.

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34

Kumagai, Naoaki, Kazuo Tanno, Tsuyoshi Nakajima, and Nobuatsu Watanabe. "Electrode reaction of niobium chalcogenides as positive electrodes for secondary lithium batteries." Journal of Electroanalytical Chemistry and Interfacial Electrochemistry 184, no. 1 (March 1985): 87–96. http://dx.doi.org/10.1016/0368-1874(85)85516-7.

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35

Xayyavong, Mingkhouan, Kittipong Tonmitr, Norrawit Tonmitr, and Eiji Kaneko. "The Scrutiny of the Insulation Breakdown Strength for the Nanocomposite Oxide Doped Epoxy Resin Insulator with Different Electrodes by Using Positive Impulse Voltage." Key Engineering Materials 705 (August 2016): 63–67. http://dx.doi.org/10.4028/www.scientific.net/kem.705.63.

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This research presents the ratio of doping nanocomposite oxides in dielectric materials for increasing the efficiency strength and endurance voltage. Tests were conducted and analyzed the characteristics of epoxy nanozinc oxides. By using positive standard impulse voltage abilities of nanocomposite oxides were used as electrical insulators-epoxy resin doped with zinc oxides nanocomposite in ratios of 0, 5, 10, 15, and 20% by weight. And the design of electrodes embeds in the specimens with 4 types of electrode, as needle electrode, point electrode, spherical electrode and the partial spherical electrode. When adjusted the impulse voltage level of 75kV to the specimen immersed in transformer oil. The experiment aforementioned to investigate the ratios damages on insulator surfaces and the number of breakdowns. The microscopes with magnification levels of 20-800X were used to view the damages on insulator surfaces. Results, it was found that regarding specimens used for doping an epoxy resin with zinc oxides nanocomposite in a ratio of 5% had high withstand insulator with electrode types. The partial spherical electrode tested with positive impulse standard voltage has destructive distance lower damage than other electrode types.

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36

Abdul Ali, Abdul Wali, and Normiza Mohamad Nor. "On the Characterisations of the Impulse Breakdown in High Resistivity Soils by Field Testing." Energies 14, no. 9 (April 23, 2021): 2401. http://dx.doi.org/10.3390/en14092401.

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This paper presents experimental results of high-current impulse tests on six ground electrode configurations. A high impulse current generator is employed to inject different magnitudes of current into these rod electrodes, under both positive and negative impulse polarities. The effect of increasing the number of rod electrodes, hence the resistance at DC or steady-state (RDC), on the impulse response of ground electrodes is analysed. From the analysis of the results, it was found that the larger the size of rod electrodes, the less current-dependent Zimpulse becomes. The percentage of reduction of impulse impedance, Zimpulse from its steady state, and RDC values are found to be independent of impulse polarity. However, as the voltage magnitudes were increased, an occurrence of breakdown was seen, with higher breakdown voltage seen in negative impulse polarity in comparison to positive impulse polarity. Relatively, the higher the breakdown voltage is, seen in the ground electrodes subjected to negative polarity, the faster the time to breakdown is.

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37

Ma, Guofu, Fengting Hua, Kanjun Sun, Enke Fenga, Hui Peng, Zhiguo Zhang, and Ziqiang Lei. "Nanostructure selenium compounds as pseudocapacitive electrodes for high-performance asymmetric supercapacitor." Royal Society Open Science 5, no. 1 (January 2018): 171186. http://dx.doi.org/10.1098/rsos.171186.

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The electrochemical performance of an energy conversion and storage device like the supercapacitor mainly depends on the microstructure and morphology of the electrodes. In this paper, to improve the capacitance performance of the supercapacitor, the all-pseudocapacitive electrodes of lamella-like Bi 18 SeO 29 /BiSe as the negative electrode and flower-like Co 0.85 Se nanosheets as the positive electrode are synthesized by using a facile low-temperature one-step hydrothermal method. The microstructures and morphology of the electrode materials are carefully characterized, and the capacitance performances are also tested. The Bi 18 SeO 29 /BiSe and Co 0.85 Se have high specific capacitance (471.3 F g –1 and 255 F g –1 at 0.5 A g –1 ), high conductivity, outstanding cycling stability, as well as good rate capability. The assembled asymmetric supercapacitor completely based on the pseudocapacitive electrodes exhibits outstanding cycling stability (about 93% capacitance retention after 5000 cycles). Moreover, the devices exhibit high energy density of 24.2 Wh kg –1 at a power density of 871.2 W kg –1 in the voltage window of 0–1.6 V with 2 M KOH solution.

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38

Yang, Ai Mei, Gui Zhong Li, Shao Ying Zhen, and Lai Jun Liu. "Electrode Interface Polarization in BaTiO₃-Based PTC Ceramics." Key Engineering Materials 697 (July 2016): 248–52. http://dx.doi.org/10.4028/www.scientific.net/kem.697.248.

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Electrodes play a vital role on the electrical properties of positive temperature coefficient (PTC) ceramics. An ohmic contract between ceramics and electrodes is necessary for the PTC effect. In this work, silver mixed aluminium electrode and pure silver electrode were pasted on BaTiO3-based PTC ceramics, which results in an ohmic contact and non-ohmic contact, respectively. Impedance spectroscopy and dielectric and conductivity properties was investigated at different temperature for the two contacts. Small difference of electrical properties was found between the two contacts above the Curie temperature. Below the Curie temperature, however, carriers could pass through the interface of ohmic contract but gather on the interface of non-ohmic contact. The latter resulted in a space charge polarization, which increased low-frequency dielectric permittivity.

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39

Kamau, G. N., and B. Munge. "Selective control and rate enhancement of reactions involving catalytic reduction of organohalides and reduced form of myoglobulin in microemulsions." Pure and Applied Chemistry 76, no. 4 (January 1, 2004): 815–28. http://dx.doi.org/10.1351/pac200476040815.

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Myoglobin (horse heart, Mb) adsorbed on carbon electrodes or in solution at platinum electrodes was used for electrocatalytic reduction of trans-1,2-dibromocyclohexane (DBCH) and trichloroacetic acid (TCA) in a bicontinuous microemulsion, prepared from sodium didodecyl sulfate (SDS) or hexadecyltrimethylammonium bromide (CTAB), tetradecane, pentanol, and water. Carbon electrodes (glassy carbon, GC, and pyrolytic graphite, PG) exhibited adsorption peaks, whereas platinum (Pt) portrayed diffusion-controlled peaks. Electrode reduction of Mb had E0' at −0.179 ± 0.013 V at GC/SDS, −0.189 ± 0.015 at GC/CTAB, and −0.562 ± 0.018 at Pt/SDS and 0.611 ± 0.008 at Pt/CTAB media.Current efficiencies for electrocatalytic reduction of TCA were higher than that for reduction of dibromocyclohexane. For both substrates, dibromocyclohexane and trichhloroacetic acid, a lowering of overpotential of at least 1.3 V was achieved. Overall, the Pt electrode exhibited higher catalytic efficiencies compared to carbon electrodes, suggesting higher surface concentration and unhindered orientation of the substrate on the Pt electrode. For DBCH, catalytic efficiencies decreased with scan rate, at carbon electrodes as expected for homogeneous solutions, whereas an average value of 2.22 ± 0.42 in SDS and 3.29 ± 0.76 in CTAB microemulsion was obtained at Pt electrodes at a scan rate range of 15 to 3000 mVs−1. Pseudo-first-order rate constants (k') for the rate-determining step (rds) involving reaction of organohalides with catalyst had an average value of 41 ±1 M−1 s−1 for reduction of DBCH/SDS and 4.8 ± 1.0 ×102 M−1 s−1 for reduction of TCA/SDS. Moreover, rate constants were higher in CTAB microemulsion, giving values of 1.5 ±0.016 ×102 and 2.75 ±0.67 × 103 M−1 s−1 for DBCH and TCA, respectively. Positive interfacial charge of the microemulsion conduits influenced catalytic reaction of catalyst and the substrate. Under the conditions of the experiment, no hydrogen evolution was observed at Pt electrodes.

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40

Cogollo, Mar, Pedro M. Balsalobre, Andrés Díaz Lantada, and Héctor Puago. "Design and Experimental Evaluation of Innovative Wire-to-Plane Fins’ Configuration for Atmosphere Corona-Discharge Cooling Devices." Applied Sciences 10, no. 3 (February 4, 2020): 1010. http://dx.doi.org/10.3390/app10031010.

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Electro-fluid-dynamic cooling devices (EFAs) are being recognized due to their enormous advantages for their application in several industrial sectors, their performance benefits from generated ionic winds and their singular features, which make them competitive with conventional fans and heatsinks. Due to the problems in the electronics industry, where traditional refrigeration systems are not effective due to their dimensions, this study analyzes an innovative arrangement based on wire-to-plane fins by direct current (DC) positive corona discharge in atmospheric air for applications. The paper focuses on optimizing the multicriteria geometry of the electrodes. Several parameters are analyzed such as the gap between emitter and ground electrodes, the electrode materials and geometry, the diameter of the high-voltage electrode and the influence of the dielectric barriers located near the corona electrode to improve heat exchange. Experimental validation shows the potential of this arrangement related to weight, volume, non-mobile parts and silence.

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41

Li, Zhuang, Hongliang Kang, Ning Che, Zhijing Liu, Pingping Li, Weiwei Li, Chao Zhang, Chun Cao, Ruigang Liu, and Yong Huang. "Effects of Electrode Reversal on the Distribution of Naproxen in the Electrospun Cellulose Acetate Nanofibers." Journal of Nanomaterials 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/360658.

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Naproxen (NAP)/cellulose acetate hybrid nanofibers were prepared by positive and reversed emitting electrodes electrospinning setups. The morphology and structure of the resultant nanofibers were characterized, and the NAP release behaviors were investigated. It was found that NAP dispersed in the CA matrix in molecular level, and no aggregation and dimers of NAP were found in the resultant NAP/CA hybrid nanofibers due to the formation of hydrogen bonds between NAP and CA. The nanofibers obtained by reversed emitting electrode electrospinning setup have a thicker diameter and a faster NAP release rate compared with those obtained by positive emitting electrode electrospinning setup. The faster drug release of NAP from nanofibers prepared by reversed emitting electrode electrospinning is due to the fact that the concentration of NAP molecules near the surface of the nanofibers is relatively higher than that of the nanofibers prepared by positive emitting electrode electrospinning setup. The effects of the electrode polarity on the distribution of drugs in nanofibers can be used to prepare hybrid electrospun fibers of different drug release rates, which may found applications in biomedical materials.

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Patil, Dipali S., Sachin A. Pawar, Hyo Jin Kim, and Jae Cheol Shin. "Hierarchical Manganese–Iron-Layered Double Hydroxide Nanosheets for Asymmetric Supercapacitors." Energies 13, no. 18 (September 4, 2020): 4616. http://dx.doi.org/10.3390/en13184616.

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This work presents a synthesis of hierarchical manganese–iron-layered double hydroxide (MnFe-LDH) nanostructured electrodes using the hydrothermal synthesis route by varying the reaction time for electrochemical energy storage applications. The electrochemical behavior of the MnFe-LDH electrodes synthesized at different reaction times was analyzed in a three-electrode cell configuration using 2 M KOH electrolyte. The uniform and well-organized MnFe-LDH nanosheet electrode (MnFe-12h) showed the maximum areal capacitance of 2013 mFcm−2 at a 5 mVs−1 scan rate, and 1886 mFcm−2 at a 25 mA applied current. Furthermore, the electrochemical behavior of MnFe-12h was examined by assembling an asymmetric cell device using activated carbon (AC) as a negative electrode and MnFe-12h as a positive electrode and it was tested in a wide voltage window range of 0.0 to 1.6 V. This asymmetric cell device achieved an appropriate energy density of 44.9 µW h cm−2 (55.01 W h kg−1), with a power density of 16 mW cm−2 (5000 W kg−1) at an applied current of 10 mA, and had a long-term cycling stability (93% capacitance retention after 5000 cycles) within the 1.6 V operating voltage window.

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43

Matemadombo, Fungisai, Nthapo Sehlotho, and Tebello Nyokong. "Effects of the number of ring substituents of cobalt carboxyphthalocyanines on the electrocatalytic detection of nitrite, cysteine and melatonin." Journal of Porphyrins and Phthalocyanines 13, no. 08n09 (August 2009): 986–97. http://dx.doi.org/10.1142/s108842460900125x.

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Cobalt phthalocyanine (CoPc), cobalt tetracarboxy phthalocyanine (CoTCPc) and cobalt octacarboxy phthalocyanine (CoOCPc), adsorbed onto glassy carbon electrodes, have been used for the electrocatalytic detection of nitrite, L-cysteine and melatonin. The modified electrodes electrocatalytically detected nitrite around 800 mV vs. Ag|AgCl , a value less positive compared to that of an unmodified glassy carbon electrode (at 950 mV vs. Ag|AgCl ) and also gave detection limits in the 10-7 M range for nitrite detection. L-cysteine was detected by the modified electrodes at potentials between 0.50 to 0.65 V vs. Ag|AgCl , with L-cysteine detection limits also in the 10-7 M range. The detection limits for melatonin ranged from 10-7 to 10-6 M. CoPc-modified electrodes displayed good separation of interferents (tryptophan and ascorbic acid) in the presence of melatonin. Analyses of commercial melatonin tablets using modified electrodes gave excellent agreement with manufacturer's value for all modified electrodes of this work.

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44

Shemer, Guy, and Yaron Paz. "Interdigitated Electrophotocatalytic Cell for Water Purification." International Journal of Photoenergy 2011 (2011): 1–7. http://dx.doi.org/10.1155/2011/596710.

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The preparation, characterization, and performance of an electrophotocatalytic cell, made of low-cost, planar interdigitated electrodes is reported hereby. The operation of the cell under small positive bias was demonstrated by photocatalytically degrading the dye rhodamine 6G in solution as well as by monitoring the degradation of self-assembled monolayer chemisorbed on the TiO2electrode. Results point out to the importance of activated oxygen species formed in the process and suggest that the short distance between the two electrodes provides a way to utilize the activated oxygen species formed at the negatively biased electrode.

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Fukuzawa, Yasushi, Keiji Yukihiro, and Ken Yamasita. "Machining Properties of Insulating ZrO₂ Ceramics Using Porous Copper Electrodes." Key Engineering Materials 443 (June 2010): 608–13. http://dx.doi.org/10.4028/www.scientific.net/kem.443.608.

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Insulating ceramics were considered as machinable material with the electrical discharge machining method using the assisting electrode method, which was proposed and advanced by the authors. The mechanical properties changed with the experimental parameters, including the physical characteristics of the workpiece and the tool electrode. In this research, sintered ZrO2-Y2O3 insulating ceramics were subjected to EDM. To investigate the effects of the porous tool electrode material on the removal rate, the porous copper cylinder material was fabricated by PECS (pulse electric current sintering) method. The relative density changed from 60 to 95 wt%. The suitable machining characteristics could be obtained with a relative density of 85% at the positive electrode polarity. The shape of electrodes was transcribed on the workpiece surface more precisely than the solid copper electrode.

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Zhu, Ming, Ding Fan, Yu Shi, and Hai Zhou. "Metal Transfer Behavior of Consumable DE-GMAW." Applied Mechanics and Materials 395-396 (September 2013): 1110–13. http://dx.doi.org/10.4028/www.scientific.net/amm.395-396.1110.

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Consumable double-electrode gas metal arc welding (consumable DE-GMAW) is a novel and high efficient welding method. According to the different polarity of two electrodes in consumable DE-GMAW, the metal transfer behaviors are analyzed by using the state force balance theory. For main torch with direct current electrode positive polarity, the arc root area is enlarged by bypass arc and increased electromagnetic force promotes main metal transfer. For bypass torch with direct current electrode negative polarity, the electromagnetic force does not work on the melting area. Only gravity force is major detaching force. The volume of bypass droplet is large and not easily detache to the weld pool.

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Roy Chowdhury, Gargi, and P. K. Mitra. "Effect of Induced Charge on the Passivity and Passivity Breakdown of 304LN Stainless Steels." Advances in Materials Science and Engineering 2011 (2011): 1–9. http://dx.doi.org/10.1155/2011/798262.

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Passivity breakdown of stainless steel by pitting in chloride environment is believed to occur at point at zero charge (pzc). So, the nature and quantity of charge on the surface plays a very important role on the breakdown of passivity, as chloride ion adsorption depends on that. In this work a DC potential was maintained between aluminium and graphite electrodes, and the aluminium electrode, in turn, was kept in the vicinity of the working electrode in the potentiostatic circuit. Both positive and negative polarity was applied on aluminium to attract or repel chloride ions in the vicinity of the working electrode. Chloride adsorption pattern on the stainless steel electrode got drastically altered due to application of DC potential on the aluminium-graphite circuit.

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González-Quijano, D., W. J. Pech-Rodríguez, L. E. Verduzco, J. I. Escalante-García, G. Vargas-Gutiérrez, and F. J. Rodríguez-Varela. "Application of the Electrophoretic Deposition Technique for the Development of Electrodes Containing a Catalyst Layer of Nanostructured Pt-Sn/C for DAFCs." MRS Advances 5, no. 57-58 (2020): 2991–3002. http://dx.doi.org/10.1557/adv.2020.379.

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AbstractA catalyst layer of Pt-Sn/C (Pt:Sn 1:1 atomic ratio) was deposited on commercial carbon cloth electrodes by electrophoretic deposition (EPD). The Pt-Sn/C nanocatalyst was synthesized by the polyol method. Three current signals were applied: i) continuous direct current (CDC); ii) positive pulsed current (PPC); and iii) asymmetric alternating current (AAC). The chemical composition analysis showed the effect of the applied signal on species transferred onto the carbon cloth to form the catalyst layers. Evaluation by SEM confirmed the effect of deposition-signal on the morphology of the catalyst layer. The CDC signal formed spherical agglomerates with irregular distribution along with carbon fibers over the electrode, showing some cracks. A cross-cut view of the electrode showed that the catalyst penetrated the carbon cloth. Meanwhile, the PPC signal promoted a better deposition of the catalyst layer over the carbon cloth surface, with a thicker and more homogeneous rough layer than CDC. In contrast, the layer developed by the AAC signal showed a morphology similar to that by CDC, suggesting the formation of a layer with low metal loading. The cross-cut view of the AAC electrode showed the formation of a highly rough layer having large areas with limited contact with the carbon cloth fibers. The electro-catalytic activity of the electrodes for the Ethanol Oxidation Reaction (EOR) was studied in acid media. The CDC electrode showed an enhanced performance for the EOR by delivering the highest current density (272 mA mg-1Pt) with the more negative onset potential (341 mV) relative to the PPC and AAC electrodes.

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Gortschakow, Sergey, Steffen Franke, Ralf Methling, Diego Gonzalez, Andreas Lawall, Erik D. Taylor, and Frank Graskowski. "Properties of Vacuum Arcs Generated by Switching RMF Contacts at Different Ignition Positions." Energies 13, no. 21 (October 26, 2020): 5596. http://dx.doi.org/10.3390/en13215596.

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The influence of initiation behavior of the drawn arc on the arc motion, on arc characteristics during the active phase, as well as on the post-arc parameters, was studied. The study was focused on arc dynamics, determination of the anode surface temperature after current interruption, and diagnostics of metal vapor density after current zero crossing. Different optical diagnostics, namely high-speed camera video enhanced by narrow-band optical filters, near infrared spectroscopy, and optical absorption spectroscopy was applied. The initiation behavior of the drawn arc had a clear influence on arc parameters. Higher local electrode temperature occurs in case of the electrodes with ignition point near the outer electrode boundary. This further causes an enhanced density of chromium vapor, even in cases with lower arc duration. The results of this study are important for design development of switching RMF contacts for future green energy applications.

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Ruth, Roger A., and Paul R. Lambert. "Comparison of Tympanic Membrane to Promontory Electrode Recordings of Electrocochleographic Responses in Patients with Meniere's Disease." Otolaryngology–Head and Neck Surgery 100, no. 6 (June 1989): 546–52. http://dx.doi.org/10.1177/019459988910000604.

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The purpose of the present study was to evaluate ECoG recordings obtained simultaneously from a transtympanic electrode and a tympanic membrane electrode In 26 patients with unilateral Meniere's disease. The ECoG recordings were examined quantitatively with regard to absolute amplitude of the summating potential and action potential. Recordings were examined qualitatively in terms of overall waveform quality and ease of component wave Identification. All patients demonstrated a clear response with both electrodes. Although the transtympanlc electrode resulted in the most robust responses in overall amplitude, the tympanic membrane electrode provided recordings equal to or, In most cases, superior to other noninvasive, extratympanic methods currently available. Furthermore, In our patient population, the likelihood of a positive (upward-going) summating potential was less for the tympanic membrane electrode recordings than for the TT electrode recordings. The major advantages of the TM electrode system are Its unique method of stimulus delivery and Its ease of application.

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Journal articles on the topic 'Electrodes positives'

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