Relevant bibliographies by topics / Morphology of electrojet

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Academic literature on the topic 'Morphology of electrojet'

Author: Grafiati
Published: 6 September 2023

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Journal articles on the topic "Morphology of electrojet"

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Bolaji, Olawale, Oluwafisayo Owolabi, Elijah Falayi, Emmanuel Jimoh, Afolabi Kotoye, Olumide Odeyemi, Babatunde Rabiu, et al. "Observations of equatorial ionization anomaly over Africa and Middle East during a year of deep minimum." Annales Geophysicae 35, no. 1 (January 20, 2017): 123–32. http://dx.doi.org/10.5194/angeo-35-123-2017.

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Abstract. In this work, we investigated the veracity of an ion continuity equation in controlling equatorial ionization anomaly (EIA) morphology using total electron content (TEC) of 22 GPS receivers and three ground-based magnetometers (Magnetic Data Acquisition System, MAGDAS) over Africa and the Middle East (Africa–Middle East) during the quietest periods. Apart from further confirmation of the roles of equatorial electrojet (EEJ) and integrated equatorial electrojet (IEEJ) in determining hemispheric extent of EIA crest over higher latitudes, we found some additional roles played by thermospheric meridional neutral wind. Interestingly, the simultaneous observations of EIA crests in both hemispheres of Africa–Middle East showed different morphology compared to that reported over Asia. We also observed interesting latitudinal twin EIA crests domiciled at the low latitudes of the Northern Hemisphere. Our results further showed that weak EEJ strength associated with counter electrojet (CEJ) during sunrise hours could also trigger twin EIA crests over higher latitudes.
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López, Ericson, Franklin Aldás, and Akimasa Yoshikawa. "Analysis of Magnetic Field Variations Produced by Equatorial Electro-Jets." Proceedings of the International Astronomical Union 13, S335 (July 2017): 125–27. http://dx.doi.org/10.1017/s1743921318000662.

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AbstractThe Equatorial Electrojet (EEJ) is a narrow band of electrons flowing from east to west at daytime at low latitudes. The electron current produces a magnetic field variation that can be measured at different latitudes. In this work, we have used the data analysis in order to quantify the solar and lunar contributions to those variations and study the morphology of the EEJ current.
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Partamies, Noora, Daniel Whiter, Kirsti Kauristie, and Stefano Massetti. "Magnetic local time (MLT) dependence of auroral peak emission height and morphology." Annales Geophysicae 40, no. 5 (October 12, 2022): 605–18. http://dx.doi.org/10.5194/angeo-40-605-2022.

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Abstract. We investigate the bulk behaviour of auroral structures and peak emission height as a function of magnetic local time (MLT). These data are collected from the Fennoscandian Lapland and Svalbard latitudes from seven identical auroral all-sky cameras (ASC) over about one solar cycle. The analysis focusses on green auroral emission, which is where the morphology is most clearly visible and the number of images is the highest. The typical peak emission height of the green and blue aurora varies from 110 km on the nightside to about 118 km in the morning MLT over the Lapland region. It stays systematically higher (at 118–120 km) at high latitudes (Svalbard) during the nighttime and reaches 140 km at around magnetic noon. During high solar wind speed (above 500 km s−1), nightside emission heights appear about 5 km lower than during slow solar wind speed (below 400 km s−1). The sign of the interplanetary magnetic field (IMF) has nearly no effect on the emission heights in the night sector, but the northward IMF causes lower emission heights at dawn over Lapland and during the noon hours over Svalbard. While the former is interpreted as a change in the particle population within the field-of-view (FoV), the latter is rather due to the movement of the cusp location due to the IMF orientation. The morning sector heights also show a pronounced difference when previously detected pulsating aurora (PsA) events have been excluded/included in the dataset, suggesting that this type of aurora is a dominant phenomenon in the morning and an important dissipation mechanism. An increase of complex auroral structures in the midnight hours agrees with the average substorm occurrence. This increase is amplified during stronger solar wind driving and during higher geomagnetic activity (as measured by auroral electrojet index, AL). During high solar wind speed, the high latitude auroral evolution shows particularly complex morphology, which is not limited to the nightside but rather only excludes the magnetic noon hours. An increase in the geomagnetic activity further enhances the structural complexity of the aurora in the morning sector.
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Mo, X. H., D. H. Zhang, L. P. Goncharenko, Y. Q. Hao, and Z. Xiao. "Quasi-16-day periodic meridional movement of the equatorial ionization anomaly." Annales Geophysicae 32, no. 2 (February 18, 2014): 121–31. http://dx.doi.org/10.5194/angeo-32-121-2014.

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Abstract. Based on the daytime location of the equatorial ionization anomaly (EIA) crest derived from GPS observations at low latitude over China during the 2005–2006 stratospheric sudden warming (SSW), a quasi-16-day periodic meridional movement of EIA crest with the maximum amplitude of about 2 degrees relative to the average location of EIA crest has been revealed. In addition, periodic variations that are in phase with the meridional EIA movement are also revealed in the equatorial electrojet (EEJ) and F2 layer peak height (hmF2) over Chinese ionosonde stations Haikou and Chongqing. The quasi-16-day periodic component in Dst index is weak, and the 16-day periodic component does not exist in F10.7 index. Such large-scale periodic meridional movement of EIA crest is likely related to the globally enhanced stratospheric planetary waves coupled with anomalous stratospheric zonal wind connected with SSW. In addition, such large-scale periodic movement of EIA should be global, and can affect the ionospheric morphology around the low-latitude belt near the EIA region. Further case analysis, simulation and theoretical studies must proceed in order to understand the periodic movements of EIA connected with the different periodic atmospheric variations.
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Kannan, Bhuvaneswari, David E. Williams, and Jadranka Travas-Sejdic. "Effect of Morphology of Conducting Polymer on DNA Sensing." Materials Science Forum 700 (September 2011): 211–14. http://dx.doi.org/10.4028/www.scientific.net/msf.700.211.

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Electrochemical DNA sensors can be constructed by understanding basic interfacial electron transfer between solid surface-electrolyte-DNA interfaces. The kinetics of this heterogeneous process can be significantly affected by the microstructure and roughness of the electrode surface. By understanding this concept, in this paper; we compared the performance of micro electrodes containing poly(Py-co-PAA) with macro electrode containing same copolymer, showing that micro electrodes are more sensitive than the macro electrodes for biosensor applications. Sensors based on the copolymer electropolymerised on both micro and macro electrodes were evaluated across a range of oligonucleotide concentrations. The interfacial electron charge transfer resistance between the solution and electrode surface was studied using electrochemical impedance spectroscopy (EIS).
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Pham Thi Thu, H., C. Amory-Mazaudier, and M. Le Huy. "Sq field characteristics at Phu Thuy, Vietnam, during solar cycle 23: comparisons with Sq field in other longitude sectors." Annales Geophysicae 29, no. 1 (January 4, 2011): 1–17. http://dx.doi.org/10.5194/angeo-29-1-2011.

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Abstract. Quiet days variations in the Earth's magnetic field (the Sq current system) are compared and contrasted for the Asian, African and American sectors using a new dataset from Vietnam. This is the first presentation of the variation of the Earth's magnetic field (Sq), during the solar cycle 23, at Phu Thuy, Vietnam (geographic latitudes 21.03° N and longitude: 105.95° E). Phu Thuy observatory is located below the crest of the equatorial fountain in the Asian longitude sector of the Northern Hemisphere. The morphology of the Sq daily variation is presented as a function of solar cycle and seasons. The diurnal variation of Phu Thuy is compared to those obtained in different magnetic observatories over the world to highlight the characteristics of the Phu Thuy observations. In other longitude sectors we find different patterns. At Phu Thuy the solar cycle variation of the amplitude of the daily variation of the X component is correlated to the F.10.7 cm solar radiation (~0.74). This correlation factor is greater than the correlation factor obtained in two observatories located at the same magnetic latitudes in other longitude sectors: at Tamanrasset in the African sector (~0.42, geographic latitude ~22.79) and San Juan in the American sector (~0.03, geographic latitude ~18.38). At Phu Thuy, the Sq field exhibits an equinoctial and a diurnal asymmetry: – The seasonal variation of the monthly mean of X component exhibits the well known semiannual pattern with 2 equinox maxima, but the X component is larger in spring than in autumn. Depending of the phase of the sunspot cycle, the maximum amplitude of the X component varies in spring from 30 nT to 75 nT and in autumn from 20 nT to 60 nT. The maximum amplitude of the X component exhibits roughly the same variation in both solstices, varying from about ~20 nT to 50 nT, depending on the position into the solar cycle. – In all seasons, the mean equinoctial diurnal Y component has a morning maximum Larger than the afternoon minimum i.e. the equivalent current flow over a day is more southward than northward. During winter, the asymmetry is maximum, it erases the afternoon minimum. At the Gnangara observatory, in Asian Southern Hemisphere, the diurnal Y pattern is opposite and the current flow is more northward. It seems that in the Asian sector, the northern and southern Sq current cells both contribute strongly to the equatorial electrojet. The pattern is different in the African and American sectors where the northern Sq current cell contribution to the equatorial electrojet is smaller than the southern one. These observations can explain the unexpected maximum of amplitude of the equatorial electrojet observed in the Asian sector where the internal field is very large. During winter the Y component flow presents an anomaly, it is always southward during the whole day and there is no afternoon northward circulation.
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Morozov, Oleg S., Anna V. Ivanchenko, Sergey S. Nechausov, and Boris A. Bulgakov. "Effect of Electrode Morphology on Performance of Ionic Actuators Based on Vat Photopolymerized Membranes." Membranes 12, no. 11 (November 7, 2022): 1110. http://dx.doi.org/10.3390/membranes12111110.

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Bucky gel electrodes are composed of morphology-determining polyvinylidene difluoride (PVDF) filled with carbon nanotubes (CNT). The electrodes are commonly fabricated via the casting of a CNT dispersion containing PVDF and ionic liquid. In this study, several pore-forming additives such as polyethylene glycol (PEG), dibutyl phthalate (DBP), and the common ionic liquid BMIMBF4 were used to control the morphology of the bucky gel electrodes. The crystalline phase type and content of PVDF in the electrodes were determined by FT-IR and DSC, respectively. SEM revealed a sponge-like structure in the case of the use of BMIMBF4 and a spherulite structure if PEG and DBP were used as additives. A strong influence of morphology on the anisotropic increase in the volume of electrodes upon impregnation with electrolyte was observed. The PEG-based electrode elongated more than the others, while the BMIMBF4-based electrode thickened to a greater extent. Ionic actuators were fabricated to experimentally reveal the effect of electrode morphology on their electromechanical efficiency. A high-precision vat photopolymerization technique was used to fabricate identical ionic membranes and minimize their influence on the properties of the actuators. The electrodes were characterized by the same porosity and electrical capacitance, while the actuators differ significantly in performance. As a result, a simple method of using pore-forming additives made it possible to increase the maximum deformation of bucky gel ionic actuators by 1.5 times by changing the morphology of the electrodes.
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Payer, Gizem, and Özgenç Ebil. "Zinc Electrode Morphology Evolution in High Energy Density Nickel-Zinc Batteries." Journal of Nanomaterials 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/1280236.

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Prismatic Nickel-Zinc (NiZn) batteries with energy densities higher than 100 Wh kg−1were prepared using Zn electrodes with different initial morphologies. The effect of initial morphology of zinc electrode on battery capacity was investigated. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) reveal that initial morphology of zinc electrode changes drastically after a few charge/discharge cycles regardless of initial ZnO powder used. ZnO electrodes prepared using ZnO powders synthesized from ZnCl2and Zn(NO3)2lead to average battery energy densities ranging between 92 Wh kg−1and 109 Wh kg−1while using conventional ZnO powder leads to a higher energy density, 118 Wh kg−1. Average discharge capacities of zinc electrodes vary between 270 and 345 mA g−1, much lower than reported values for nano ZnO powders in literature. Higher electrode surface area or higher electrode discharge capacity does not necessarily translate to higher battery energy density.
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Mungufeni, Patrick, John Bosco Habarulema, Yenca Migoya-Orué, and Edward Jurua. "Statistical analysis of the correlation between the equatorial electrojet and the occurrence of the equatorial ionisation anomaly over the East African sector." Annales Geophysicae 36, no. 3 (June 13, 2018): 841–53. http://dx.doi.org/10.5194/angeo-36-841-2018.

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Abstract. This study presents statistical quantification of the correlation between the equatorial electrojet (EEJ) and the occurrence of the equatorial ionisation anomaly (EIA) over the East African sector. The data used were for quiet geomagnetic conditions (Kp ≤ 3) during the period 2011–2013. The horizontal components, H, of geomagnetic fields measured by magnetometers located at Addis Ababa, Ethiopia (dip lat. ∼1∘ N), and Adigrat, Ethiopia (dip lat. ∼6∘ N), were used to determine the EEJ using differential techniques. The total electron content (TEC) derived from Global Navigation Satellite System (GNSS) signals using 19 receivers located along the 30–40∘ longitude sector was used to determine the EIA strengths over the region. This was done by determining the ratio of TEC over the crest to that over the trough, denoted as the CT : TEC ratio. This technique necessitated characterisation of the morphology of the EIA over the region. We found that the trough lies slightly south of the magnetic equator (0–4∘ S). This slight southward shift of the EIA trough might be due to the fact that over the East African region, the general centre of the EEJ is also shifted slightly south of the magnetic equator. For the first time over the East African sector, we determined a threshold daytime EEJ strength of ∼ 40 nT that is mostly associated with prominent EIA occurrence during a high solar activity period. The study also revealed that there is a positive correlation between daytime EEJ and EIA strengths, with a strong positive correlation occurring during the period 13:00–15:00 LT. Keywords. Ionosphere (equatorial ionosphere)
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Jaffe, Debra M., Nancy P. Solomon, Robert A. Robinson, Henry T. Hoffman, and Erich S. Luschei. "Comparison of Concentric Needle Versus Hooked-Wire Electrodes in the Canine Larynx." Otolaryngology–Head and Neck Surgery 118, no. 5 (May 1998): 655–62. http://dx.doi.org/10.1177/019459989811800515.

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BACKGROUND: The use of a specific electrode type in laryngeal electromyography has not been standardized. Laryngeal electromyography is usually performed with hooked-wire electrodes or concentric needle electrodes. Hooked-wire electrodes have the advantage of allowing laryngeal movement with ease and comfort, whereas the concentric needle electrodes have benefits from a technical aspect and may be advanced, withdrawn, or redirected during attempts to appropriately place the electrode. OBJECTIVES: This study examines whether hooked-wire electrodes permit more stable recordings than standard concentric needle electrodes at rest and after large-scale movements of the larynx and surrounding structures. A histologic comparison of tissue injury resulting from placement and removal of the two electrode types is also made by evaluation of the vocal folds. METHODS: Electrodes were percutaneously placed into the thyroarytenoid muscles of 10 adult canines. Amplitude of electromyographic activity was measured and compared during vagal stimulation before and after large-scale laryngeal movements. Signal consistency over time was examined. Animals were killed and vocal fold injury was graded and compared histologically. RESULTS: Waveform morphology did not consistently differ between electrode types. The variability of electromyographic amplitude was greater for the hooked-wire electrode ( p < 0.05), whereas the mean amplitude measures before and after large-scale laryngeal movements did not differ ( p > 0.05). Inflammatory responses and hematoma formation were also similar. CONCLUSIONS: Waveform morphology of electromyographic signals registered from both electrode types show similar complex action potentials. There is no difference between the hooked-wire electrode and the concentric needle electrode in terms of electrode stability or vocal fold injury in the thyroarytenoid muscle after large-scale laryngeal movements. (Otolaryngol Head Neck Surg 1998;118:655–62.)
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Dissertations / Theses on the topic "Morphology of electrojet"

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Melin, Tim. "Morphology of electrodeposited Na on Al electrodes." Thesis, Uppsala universitet, Strukturkemi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-390801.

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The demand for alternative secondary batteries to lithium-ion batteries (LIBs) grows. Sodium-ion batteries (SIBs) have been studied for many years and could replace LIBsfor some application. Metallic anodes for both LIBs and SIBs are interesting due totheir high energy densities. Several aspects such as reactivity, stability and depositionmorphology must be properly addressed before metallic Na could be considered apossible anode material. This study aims to evaluate deposition of Na on Alelectrodes using fundamental electrochemical theories. Na deposition was studiedusing pouch cells and sodium triflate (NaOTf) in dimethyl glycol ether (diglyme) aselectrolyte. Galvanostatic deposition using different current densities, electrolyteconcentrations and potential pulses prior to galvanostatic deposition were tested. Theelectrochemical methods used in this study were galvanostatic deposition andchronoamperometry. The morphology of deposited Na was analyzed with ex-situscanning electron microscopy (SEM). A decrease of the size of deposited Na islandswas observed for both increasing current density and decreasing electrolyteconcentration. Fluctuations and poor stability in the deposition potential wereobtained when decreasing the electrolyte concentration under 0.5 M and also whenincreasing the current density over 1 mA cm-2. The most homogeneous depositionwas obtained with a 1030 ms potential pulse amplitude (-3 V vs. Na+/Na) prior togalvanostatic deposition (1 mA cm-2, 0.5 mAh cm-2) using 0.1 M NaOTf in diglyme aselectrolyte. Reproducibility was a major issue in this study and further investigation ofseveral parameters is needed.
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McDermott, Christie Allred. "Morphology and electrochemical reactivity of glassy carbon electrodes /." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487780393268822.

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Hua, Xiao. "Structure, morphology and reaction mechanisms of novel electrode materials for lithium-ion batteries." Thesis, University of Cambridge, 2015. https://www.repository.cam.ac.uk/handle/1810/252637.

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For the Li1+xV1-xO2 materials, the amount of excess Li does not change the average crystal structure; however, it alters the cycling performance greatly. This suggests that the local structure governs the electrochemical behaviour. This motivated us to employ the pair distribution function (PDF) technique to probe the local structure. The analyses show the displacements of V3+ form trimers. A structure model for the stoichiometric LiVO2 incorporating the V3+ distortion was constructed and refined, to assist in the assignment of the Li sites revealed by the 6Li nuclear magnetic resonance (NMR) results. For the TiO2-B materials, previous investigations of nanostructured phases suggested the Li insertion mechanism of these materials has a morphological dependence. However, the morphology of the nanoparticles, which to date shows the best cycling performance among all the TiO2 phases with various morphologies, has not been well studied due to the technical challenges which arise from the nature of the diffraction technique and the limited particle sizes. We therefore employed techniques including small-angle X-ray scattering (SAXS) and PDF analyses, to provide an accurate description of the morphology for these nanoparticles. Combining advanced structure modelling, we demonstrated that the nanoparticles adopt an oblate shape with the minor-axis along the b-axis. For the CuF2 conversion material, which theoretically has an exceptionally high specific energy density, behaves differently in practice when compared with other fluorides, such as FeF2 and NiF2. The mechanism underlying its unique electrochemical performance and poor reversibility were investigated via a variety of characterization methods, including cyclic voltammetry (CV), X-ray absorption near edge structure (XANES), PDF and NMR spectroscopy. We demonstrated that Cu dissolution takes place upon charge, associated with the consumption of the LiF phase via the formation of a Cu1+ intermediate. Such side reaction prevents Cu from transforming back to CuF2, leading to negligible capacities in subsequent cycles and making this material challenging to use in a rechargeable battery.
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Hegge, Friedemann [Verfasser], Stefan [Akademischer Betreuer] Glunz, and Simon [Akademischer Betreuer] Thiele. "Morphology analysis and development of electrodes for polymer electrolyte membrane water electrolyzers and fuel cells." Freiburg : Universität, 2020. http://d-nb.info/1218464089/34.

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Liu, Shuai Verfasser], Werner [Akademischer Betreuer] [Lehnert, and Lorenz [Akademischer Betreuer] Singheiser. "Morphology and degradation of high temperature polymer electrolyte fuel cell electrodes / Shuai Liu ; Werner Karl Josef Lehnert, Lorenz Singheiser." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/1211487881/34.

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Vonau, Corinna. "Morphologie und Degradation von O2, Pt│YSZ-Elektrodensystemen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-183965.

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In der vorliegenden Arbeit wird erstmals systematisch der Einfluss von gasförmigen und festen Verunreinigungen auf das O2, Pt│YSZ- Elektrodensystem am praxisnahen Beispiel der Lambdasonde untersucht. Dazu wurden Festelektrolyt- und Elektrodenmaterialien unterschiedlicher Zusammensetzung und Morphologie den realen Abgasbedingungen nachempfundenen, chemischen und physikalischen Einflüssen ausgesetzt und in Bezug auf Langzeitstabilität, Sensitivität und Wirkmechanismen untersucht. Im Einzelnen lag der Fokus der Untersuchungen auf zwei Ausführungsformen von Elektroden, die sich vor allem durch mikro- bzw. nanoskalige Partikelgrößenverteilungen sowie der Platin/YSZ-Zusammensetzung unterschieden und als Mikro- bzw. Nano-Elektrode bezeichnet wurden. Der Einfluss von Siliciumdioxid als gezielt dem Festelektrolyten beigemischte intrinsische Vergiftung sollte in Wechselwirkung zu den extrinsischen Verunreinigungen wie Natriumionen, Wasserdampf und Phosphorpentoxid untersucht werden. Im Unterschied zu den in der Literatur betrachteten, vereinfachten Modellsystemen konnten damit erstmals Wechselwirkungen beschrieben werden, die zu einem tieferen Verständnis des realen Sensorverhaltens, vor allem der Degradation beitragen. Insbesondere ist es gelungen, ein Modell für die Sauerstoffreaktion an geschädigten Elektroden aufzustellen. Neben der bekannten elektrochemischen Reduktion von Sauerstoff spielen die Transportvorgänge an der Elektrodenoberfläche eine entscheidende Rolle, über die in der Literatur bisher nur wenig bekannt war.
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Reddi, Rahul. "In-situ characterization of Li-ion battery electrodes using atomic force microscopy." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1524215477787917.

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Oyarce, Alejandro. "Electrode degradation in proton exchange membrane fuel cells." Doctoral thesis, KTH, Tillämpad elektrokemi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-133437.

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The topic of this thesis is the degradation of fuel cell electrodes in proton exchange membrane fuel cells (PEMFCs). In particular, the degradation associated with localized fuel starvation, which is often encountered during start-ups and shut-downs (SUs/SDs) of PEMFCs. At SU/SD, O2 and H2 usually coexist in the anode compartment. This situation forces the opposite electrode, i.e. the cathode, to very high potentials, resulting in the corrosion of the carbon supporting the catalyst, referred to as carbon corrosion. The aim of this thesis has been to develop methods, materials and strategies to address the issues associated to carbon corrosion in PEMFC.The extent of catalyst degradation is commonly evaluated determining the electrochemically active surface area (ECSA) of fuel cell electrode. Therefore, it was considered important to study the effect of RH, temperature and type of accelerated degradation test (ADT) on the ECSA. Low RH decreases the ECSA of the electrode, attributed to re-structuring the ionomer and loss of contact with the catalyst.In the search for more durable supports, we evaluated different accelerated degradation tests (ADTs) for carbon corrosion. Potentiostatic holds at 1.2 V vs. RHE were found to be too mild. Potentiostatic holds at 1.4 V vs. RHE were found to induce a large degree of reversibility, also attributed to ionomer re-structuring. Triangle-wave potential cycling was found to irreversibly degrade the electrode within a reasonable amount of time, closely simulating SU/SD conditions.Corrosion of carbon-based supports not only degrades the catalyst by lowering the ECSA, but also has a profound effect on the electrode morphology. Decreased electrode porosity, increased agglomerate size and ionomer enrichment all contribute to the degradation of the mass-transport properties of the cathode. Graphitized carbon fibers were found to be 5 times more corrosion resistant than conventional carbons, primarily attributed to their lower surface area. Furthermore, fibers were found to better maintain the integrity of the electrode morphology, generally showing less degradation of the mass-transport losses. Different system strategies for shut-down were evaluated. Not doing anything to the fuel cell during shut-downs is detrimental for the fuel cell. O2 consumption with a load and H2 purge of the cathode were found to give around 100 times lower degradation rates compared to not doing anything and almost 10 times lower degradation rate than a simple air purge of the anode. Finally, in-situ measurements of contact resistance showed that the contact resistance between GDL and BPP is highly dynamic and changes with operating conditions.
Denna doktorsavhandling behandlar degraderingen av polymerelektrolytbränslecellselektroder. polymerelektrolytbränslecellselektroder. Den handlar särskilt om nedbrytningen av elektroden kopplad till en degraderingsmekanism som heter ”localized fuel starvation” oftast närvarande vid uppstart och nedstängning av bränslecellen. Vid start och stopp kan syrgas och vätgas förekomma samtidigt i anoden. Detta leder till väldigt höga elektrodpotentialer i katoden. Resultatet av detta är att kolbaserade katalysatorbärare korroderar och att bränslecellens livslängd förkortas. Målet med avhandlingen har varit att utveckla metoder, material och strategier för att både öka förståelsen av denna degraderingsmekanism och för att maximera katalysatorbärarens livslängd.Ett vanligt tillvägagångsätt för att bestämma graden av katalysatorns degradering är genom mätning av den elektrokemiskt aktiva ytan hos bränslecellselektroderna. I denna avhandling har dessutom effekten av temperatur och relativ fukthalt studerats. Låga fukthalter minskar den aktiva ytan hos elektroden, vilket sannolikt orsakas av en omstrukturering av jonomeren och av kontaktförlust mellan jonomer och katalysator.Olika accelererade degraderingstester för kolkorrosion har använts. Potentiostatiska tester vid 1.2 V mot RHE visade sig vara för milda. Potentiostatiska tester vid 1.4 V mot RHE visade sig däremot medföra en hög grad av reversibilitet, som också den tros vara orsakad av en omstrukturering av jonomeren. Cykling av elektrodpotentialen degraderade istället elektroden irreversibelt, inom rimlig tid och kunde väldigt nära simulera förhållandena vid uppstart och nedstängning.Korrosionen av katalysatorbäraren medför degradering av katalysatorn och har också en stor inverkan på elektrodens morfologi. En minskad elektrodporositet, en ökad agglomeratstorlek och en anrikning av jonomeren gör att elektrodens masstransportegenskaper försämras. Grafitiska kolfibrer visade sig vara mer resistenta mot kolkorrosion än konventionella kol, främst p.g.a. deras låga ytarea. Grafitiska kolfibrer visade också en förmåga att bättre bibehålla elektrodens morfologi efter accelererade tester, vilket resulterade i lägre masstransportförluster.Olika systemstrategier för nedstängning jämfördes. Att inte göra något under nedstängning är mycket skadligt för bränslecellen. Förbrukning av syre med en last och spolning av katoden med vätgas visade 100 gånger lägre degraderingshastighet av bränslecellsprestanda jämfört med att inte göra något alls och 10 gånger lägre degraderingshastighet jämfört med spolning av anoden med luft. In-situ kontaktresistansmätningar visade att kontaktresistansen mellan bipolära plattor och GDL är dynamisk och kan ändras beroende på driftförhållandena.

QC 20131104

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Gcilitshana, Oko Unathi. "Supercapacitor electrode materials based on nanostructured conducting polymers and metal oxides." Thesis, University of the Western Cape, 2013. http://hdl.handle.net/11394/3532.

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Hsu, Chia-wei, and 許家瑋. "Electrochemical and in-situ surface morphology characteristics of radical polymer brushes for thin-film electrodes." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/22926789529737538490.

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碩士
國立中山大學
化學系研究所
104
We report a novel approach to study the electrochemical performance of nitroxide radical polymer brushes for thin-film electrodes, in association with the in-situ surface morphology characteristics. In this thesis, we synthesized non-cross-linked nitroxide radical polymer brushes as the positive electrode material for thin-film electrodes via surface-initiated atom transfer radical polymerization (SI-ATRP), which is an effective method to produce smoothly surfaced organic radical polymer brushes with different grafting densities. After SI-ATRP, the covalent bonds between the nitroxide polymers and the conducting substrate are formed, which not only prevent the organic polymer from dissolving into organic electrolyte solution but also improve the cycle life performance of batteries. To understand the correlation between the density of surface-initiator and the amount of polymer chains via calculations of grafting density, we examined the electrochemical performance and the morphology of nitroxide radical polymers by varying their grafting densities. The polymer brushes with different grafting densities are characterized by water contact angle goniometer, atomic force microscope (AFM) and electron spectroscopy for chemical analysis (ESCA), along with electrochemistry techniques such as cyclic voltammetry (CV) and chronopotentiometry (CP). For further study of the mechanism in the polymer layer during electrochemical reactions within designated voltage ranges, in-situ measurements are performed by combining AFM and chronoamperometry (CA). The experimental results show that at 1% initiator composition polymer brushes exhibit better electrochemical performance, and the swelling effect in this electrolyte is also more obvious, implying an enhanced motion of polymer chains. Moreover, the space between ionic channels is enlarged by lowing the grafting density, which leads to a faster ionic diffusion rate. Through in-situ measurements, we found that polymer brushes at 1% initiator composition possess larger variation in thickness than at 100% initiator composition, and the value of apparent diffusion coefficients of polymer brushes reaches its maximum at 1% initiator composition as well, which are both in agreement with the molecular dynamic stimulation results. This study provides direct evidence showing that polymer brushes at 1% initiator composition have larger ionic-channel space, allowing more rapid passage of the anions.
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Book chapters on the topic "Morphology of electrojet"

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Srinivasan, Venkat, Kenneth Higa, Pallab Barai, and Yuanyuan Xie. "Computational Modeling of Morphology Evolution in Metal-Based Battery Electrodes." In Handbook of Materials Modeling, 1193–219. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-319-44677-6_87.

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Srinivasan, Venkat, Kenneth Higa, Pallab Barai, and Yuanyuan Xie. "Computational Modeling of Morphology Evolution in Metal-Based Battery Electrodes." In Handbook of Materials Modeling, 1–27. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-42913-7_87-1.

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Popov, Konstantin I., Predrag M. Živković, and Nebojša D. Nikolić. "The Effect of Morphology of Activated Electrodes on Their Electrochemical Activity." In Modern Aspects of Electrochemistry, 163–213. New York, NY: Springer New York, 2010. http://dx.doi.org/10.1007/978-1-4419-5589-0_4.

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Pouchko, S. V., A. K. Ivanov-Schitz, T. L. Kulova, A. M. Skundin, and E. P. Turevskaya. "Morphology Control of Electrode Materials for Li Batteries through Sol-Gel Technique." In New Trends in Intercalation Compounds for Energy Storage, 493–96. Dordrecht: Springer Netherlands, 2002. http://dx.doi.org/10.1007/978-94-010-0389-6_36.

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Alvisi, Marco, Giovanna Galtieri, L. Giorgi, Emanuele Serra, Tiziana Di Luccio, and R. Giorgi. "Evolution of Pt Nanoclusters Morphology on PEMFC Electrode due to Methanol Oxidation Reaction Studied by Electron Microscopy and Synchrotron Grazing Incidence X-Ray Diffraction." In Advances in Science and Technology, 181–86. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/3-908158-07-9.181.

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Adarakatti, Prashanth S., and Sumedha H. N. "MXenes based 2D nanostructures for supercapacitors." In Electrochemistry, 261–303. The Royal Society of Chemistry, 2023. http://dx.doi.org/10.1039/bk9781839169366-00261.

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A supercapacitor is made up of three parts: separator, electrolyte, and electrodes. A supercapacitor's performance depends on electrodes with high porosity, chemical stability, and low electrical resistivity. MXenes are getting a lot of attention because of their high electrical conductivity, good mechanical properties, and Faraday pseudocapacitive charge storage mechanism. They are being used in supercapacitor applications. MXenes electrochemical characteristics are very advantageous for energy storage applications. There are three different mechanisms for supercapacitors, which will be discussed completely in this chapter. Furthermore, MXene performance can be increased by modifying the surface groups, interlayer structures, electrode morphology, or by manufacturing a composite with an additional functional material. Manufacture of the MXene electrode for testing and analysis is a vital step in getting a supercapacitor with good performance. Choosing a good blend of materials to accompany MXene is also a vital step. It's hard to find anything else like MXenes when it comes to appealing and unique properties like high electronic conductivity, tunable layer structure, and chemistry.
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Liang, Hong, Hong Huang, Liying Zhao, Qingchun Wang, Yangmin Ren, Youli Yang, Qiang Zheng, Yi Liu, and Jie Lv. "Preparation of Co-TiO2 Nanotube Array Electrode for the Electrocatalytic Degradation of Chlorine-Containing Wastewater." In Advances in Transdisciplinary Engineering. IOS Press, 2022. http://dx.doi.org/10.3233/atde220332.

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Shale gas fracturing flowback fluid is produced during shale gas exploitation, and its complex composition and high chloride content result in limited efficiency of conventional technology. In this work, the Co-TiO2 nanotube array (Co-TiO2 NTAs) electrode with high chlorine evolution activity was successfully prepared by electrodeposition for the treatment of containing chlorine PAM simulated wastewater. The internal morphology, crystal structure, and electrochemical characteristics of the nanotubes were analyzed by scanning electron microscopy, X-ray diffraction, energy dispersive spectrometry, and linear sweep voltammetry. The electrochemical catalytic oxidation activity toward chlorine evolution reaction and degradation against polyacrylamide (PAM) in chlorine-containing wastewater were investigated. The results demonstrated that the chlorine evolution potential of the TiO2 NTAs electrode was decreased after loading 0.0333 mg/cm2 of cobalt by bipolar pulse electrodeposition. The results showed that the removal rate of chemical oxygen demand (CODcr) was 62.7% and the yield of active chlorine (ACl) was 45.2 mg/L after 1 hour of electrolysis, which were attributed to the excellent catalytic performance of the novel electrodes for the degradation of polyacrylamide. Combined with the characterization results of GC-MS and IR, the degradation mechanism of PAM was briefly described. The results indicated that the novel Co-TiO2 NTAs electrodes have a broad application prospect in electrochemical oxidation-catalytic degradation of high chlorine containing wastewater.
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Rozman, Martin, and Miha Lukšič. "Morphology and Functionalization of Metal Foils and Other Surfaces for Electrochemical Applications." In Handbook of Research on Tribology in Coatings and Surface Treatment, 359–89. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-7998-9683-8.ch015.

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Electrochemical applications had their first major impact in the late 20th century with the development of improved energy storage and conversion systems such as lithium-ion batteries, organic-inorganic dye-sensitized solar cells, and even e-ink displays. Depending on the requirements, the electrodes can be made of different materials, such as metal or alloy sheets, foils, bars or conductive ceramics, conductive polymers, etc. In this chapter, methods for surface functionalization and characterization of metallic and non-metallic surfaces used as electrode substrates are presented. The focus is on the use of metal foils in lithium-ion batteries and especially in the novel architecture of optoelectronic devices – from electrochromic and photovoltaic devices to biosensors.
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Shao, Godlisten N., and Talam E. Kibona. "Mesoporous Electrodes for Supercapacitors." In Morphology Design Paradigms for Supercapacitors, 115–29. CRC Press, 2019. http://dx.doi.org/10.1201/9780429263347-6.

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Kalivel, Parameswari. "Treatment of Textile Dyeing Waste Water Using TiO2/Zn Electrode by Spray Pyrolysis in Electrocoagulation Process." In Dyes and Pigments - Novel Applications and Waste Treatment. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.95325.

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An alternative form of treatment for the remediation of textile waste water, electrocoagulation (EC) methods are used. This work deals mainly with the treatment of waste water for textile dyeing preceded by the use of wastewater. The goal of the proposed study is to evaluate the efficiency of the electrocoagulation process using TiO2/Zn electrodes using TiCl3 via spray pyrolysis. The surface morphology of the electrode was studied by SEM, XRD and EDS analysis. The efficiency of electrocoagulation treatment process to treat synthetic waste water containing Coralene Navy RDRLSR, Coralene Red 3G, Rubru RD GLFI dye was studied. The effect of parameters such as current density, influence of effluent pH, supporting electrolyte NaCl concentration, and EC time on dye removal efficiency were investigated. The result indicates that this process is very efficient and was able to achieve color removal (99.5%) at pH 8.5 and 0.15 A in 10 minutes.
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Conference papers on the topic "Morphology of electrojet"

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Jibhakate, Piyush D., and George J. Nelson. "Fabrication and Characterization of Nanostructured Cathodes for Li-Ion Batteries." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-67873.

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Li-ion batteries have emerged as a leading energy storage technology for several applications including portable electronics devices and electric vehicles. Rigorous efforts are made to develop these batteries with higher energy density, higher power density, and better cycling stability while reducing cost and environmental impact. To better understand how electrode microstructure contributes to the electrode performance, the spinel LiMn2O4 (LMO) cathode material was prepared using a template-assisted sol-gel synthesis method. This method involves soaking of polycarbonate template membranes in the precursor solution followed by drying, to remove the solvent. The dried templates containing precursor materials were etched in an oxygen plasma to remove the template, and the nanostructured electrode formed was then calcined to convert these nanostructures to spinel LiMn2O4. Simultaneously, powdered LMO was prepared using the same synthesis procedure, but without the aid of a template to control electrode morphology. A series of tests were performed to study the effect of processing conditions on the structure and morphology of the nanostructured electrodes. The resulting electrodes were characterized using X-ray diffraction (XRD) and scanning electron microscope (SEM) in support of efforts to understand the effects of process parameters on the electrochemical performance of the electrode. The template assisted synthesis approach yielded an electrode of well-defined nanotubules. Extending the template soaking time was found to provide better definition of individual tubule structures. Increasing calcination temperature was found to create a better defined spinel structure for the LMO. These observations provide insight into process parameters relevant to electrode preparation and substrate selection when producing nanostructured electrodes using template-assisted methods.
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Nelson, George J., Comas Haynes, and William Wepfer. "A Fractal Approach for Modeling SOFC Electrode Mass Transport." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-12870.

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Fractal modeling approaches are common in the study of porous media and may be applied to describe pore surface morphology and network topology within a porous medium. Fractal structures can serve as templates for the pore structure and allow for the more detailed examination of diffusion phenomena within pore structures. In the present work a fractal pore morphology model is applied toward modeling diffusion within the electrochemically active region of an SOFC electrode. The porous electrode is separated into bulk and electrochemically active regions. Within the bulk electrode a one-dimensional model is applied based on the dusty-gas formalism assuming volume average microstructural parameters. The electrochemically active region is modeled using a two-dimensional finite element model based on a Koch pore cross-section as a fractal template. This fractal model is compared to a one-dimensional transport model applying the common assumption of a planar reaction zone. Performance variations that may exist for electrodes with the same average bulk properties are investigated in initial studies. These studies allow for exploration of the merits of fractal approaches in modeling diffusive transport within porous SOFC electrodes.
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Koraishy, Babar M., Sam Solomon, Jeremy P. Meyers, and Kristin L. Wood. "Parametric Investigations of Direct Methanol Fuel Cell Electrodes Manufactured by Spraying." In ASME 2011 9th International Conference on Fuel Cell Science, Engineering and Technology collocated with ASME 2011 5th International Conference on Energy Sustainability. ASMEDC, 2011. http://dx.doi.org/10.1115/fuelcell2011-54824.

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Manufacture of fuel cell electrodes by the thin-film method was originally proposed by Wilson et al. [1, 2] for proton-exchange membrane fuel cells (PEMFCs). This technology was subsequently utilized for the manufacture of direct methanol fuel cell (DMFC) electrodes by Ren et al. [3]. Key processing steps in the thin-film process are catalyst ink formulation and its application. The catalyst ink is typically composed of supported or unsupported catalysts, binder (ionomer), solvents and additives. Rheological properties of the ink, amount of binder, and choice of solvents are tuned to match the particular ink application process used to fabricate the electrode, as each coating process has its own unique requirements. Besides affecting the coating process, the choice and ratios of these components can significantly affect the electrochemical performance of the electrode. In this study, catalyst inks are designed and investigated for the spraying process, for utilization in the continuous fabrication of DMFC electrodes. For this purpose, the effect of the binder (ionomer) content on the performance of the electrodes is studied in detail. Decal-transfer electrodes are fabricated on a custom-built automated spraying apparatus with individually specified anode and cathode binder contents, and assembled to form a catalyst coated membrane (CCM) type membrane electrode assembly (MEA). These electrodes are rigorously tested to specifically identify their electrochemical performance, catalyst utilization and electrode morphology.
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Ye, F. X., A. Ohmori, and C. J. Li. "The Photoresponse and Donor Concentration of Plasma Sprayed TiO2 and TiO2-ZnO Electrodes." In ITSC2004, edited by Basil R. Marple and Christian Moreau. ASM International, 2004. http://dx.doi.org/10.31399/asm.cp.itsc2004p0922.

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Abstract The photoelectrochemical characteristics of plasma sprayed porous TiO2, TiO2-5%ZnO and TiO2-10%ZnO electrodes in 0.1N NaOH solution were studied through a three-electrode cell system. The microstructure, morphology and composition of the electrodes were analyzed using electron probe surface roughness analyzer (ERA-8800FE), scanning electron microscope (SEM) and X-ray diffraction. The results showed that the sprayed electrodes had a porous microstructure, which was affected by the plasma spraying parameters and composition of the powders. TiO2-ZnO electrodes consisted of anatase TiO2, rutile TiO2 and Zn2Ti3O8 phase. The photoresponse characteristics of the plasma sprayed electrodes were comparable to that of single crystal TiO2, but the breakdown voltage was approximate to 0.5V (vs. SCE). The short-circuit photocurrent density increased with a decrease of donor concentration, which was calculated according to Garner-Bulter model. For the lowest donor concentration of a TiO2-5%ZnO electrode prepared under the arc current of 600A, the short-circuit photocurrent density was approximately 0.4mA/cm2 higher than that of the TiO2 electrodes under 30mW/cm2 xenon light irradiation. The photocurrent density increased linearly with light intensity.
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Chiu, W. K. S., A. V. Virkar, K. L. Reifsnider, F. Rabbi, and Q. Liu. "HeteroFoaMs: Electrode Modeling in Nano-Structured Heterogeneous Materials for Energy Systems." In ASME 2011 9th International Conference on Fuel Cell Science, Engineering and Technology collocated with ASME 2011 5th International Conference on Energy Sustainability. ASMEDC, 2011. http://dx.doi.org/10.1115/fuelcell2011-54950.

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Heterogeneous Functional Materials, e.g., “HeteroFoaMs” are at the heart of countless energy systems, including (from left to right below) heat storage materials (a), batteries (b), solid oxide fuel cells (c), and polymer electrolyte fuel cells (d). HeteroFoaMs are generally nano-structured and porous to accommodate transport of gasses or fluids, and must be multi-functional (i.e., active operators on mass, momentum, energy or charge, in combinations). This paper will discuss several aspects of modeling the relationships between the constituents and microstructure of these material systems and their device functionalities. Technical advances based on these relationships will also be identified and discussed. Three major elements of the general problem of how to model HeteroFoaM electrodes will be addressed. Modeling approaches for ionic charge transfer with electrochemistry in the nano-structured porosity of the electrode will be discussed. Second, the effect of morphology and space charge on conduction through porous doped ceria particle assemblies, and their role in electrode processes will be modeled and described. And third, the effect of local heterogeneity and morphology on charge distributions and polarization in porous dielectric electrode materials will be analyzed using multi-physics field equations set on the details of local morphology. Several new analysis methods and results, as well as experimental data relating to these approaches will be presented. The value, capabilities, and limitations of the approaches will be evaluated.
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Ahmed, Riaz, and Kenneth Reifsnider. "Study of Influence of Electrode Geometry on Impedance Spectroscopy." In ASME 2010 8th International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2010. http://dx.doi.org/10.1115/fuelcell2010-33209.

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Electrochemical Impedance Spectroscopy (EIS) is a powerful and proven tool for analyzing AC impedance response. A conventional three electrode EIS method was used to perform the investigation in the present study. Saturated potassium chloride solution was used as the electrolyte and three different material rods were used as working electrodes. Different configurations of electrode area were exposed to the electrolyte as an active area to investigate electrode geometry effects. Counter to working electrode distance was also altered while keeping the working electrode effective area constant to explore the AC response dependence on the variation of ion travel distance. Some controlled experiments were done to validate the experimental setup and to provide a control condition for comparison with experimental results. A frequency range of 100 mHz to 1 MHz was used for all experiments. In our analysis, we have found a noteworthy influence of electrode geometry on AC impedance response. For all electrodes, impedance decreases with the increase of effective area of the electrolyte. High frequency impedance is not as dependent on geometry as low frequency response. The observed phase shift angle drops in the high frequency region with increased working electrode area, whereas at low frequency the reverse is true. Resistance and capacitive reactance both decrease with an increase of area, but resistance response is more pronounce than reactance. For lower frequencies, small changes in working area produce very distinctive EIS variations. Electrode material as well as geometry was systematically varied in the present study. From these and other studies, we hope to develop a fundamental foundation for understanding specific changes in local geometry in fuel cell (and other) electrodes as a method of designing local morphology for specific performance.
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Park, Jonghyun, Sangmin Lee, John Hoffmann, and Ann Marie Sastry. "Study of the Effect of Electrode Microstructures on Battery Performance." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-52601.

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Battery performance reflects the transport and kinetics of related species within the microstructures of battery’s electrode. However, the current homogenized battery models lack detailed morphology of the internal structures of electrodes. In this work, a multiscale battery simulation tool is developed. This model is capable of capturing the impact of microstructures of electrodes on battery performance, by adapting the variational multiscale principle. The developed model is verified through the direct numerical solutions, and compared with the conventional pseudo-2D (P2D) model method. The model has revealed more dynamic battery behaviors related to the variation of the microstructure, such as particle shape, tortuosity, and material composition, while the corresponding result from P2D shows a monotonous change within different structures.
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Morovatiyan, Mohammadrasool, Martia Shahsavan, Mengyan Shen, and J. Hunter Mack. "Investigation of the Effect of Electrode Surface Roughness on Spark Ignition." In ASME 2018 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/icef2018-9691.

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Lean-burn engines are important due to their ability to reduce emissions, increase fuel efficiency, and mitigate engine knock. In this study, the surface roughness of spark plug electrodes is investigated as a potential avenue to extend the lean flammability limit of natural gas. A nano-/micro-morphology modification is applied on surface of the spark plug electrode to increase its surface roughness. High-speed Z-type Schlieren visualization is used to investigate the effect of the electrode surface roughness on the spark ignition process in a premixed methane-air charge at different lean equivalence ratios. In order to observe the onset of ignition and flame kernel behavior, experiments were conducted in an optically accessible constant volume combustion chamber at ambient pressures and temperatures. The results indicate that the lean flammability limit of spark-ignited methane can be lowered by modulating the surface roughness of the spark plug electrode.
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Akle, Barbar J., and Donald J. Leo. "Investigation of Extensional Actuation Strain in Ionomeric Polymer Transducers." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-80220.

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Ionomeric polymer transducers have received considerable attention in the past ten years due to their ability to generate large bending strain and moderate stress at low applied voltages. Bending transducers made of an ionomeric polymer membrane sandwiched between two flexible electrodes deform through the expansion of one electrode and contraction of the opposite electrode due to cation displacement. This is similar to a bimorph type actuation. In this study we report actuation through the thickness of the membrane, leading to the potential of a new actuation mechanism for ionomeric polymer materials. Several experiments are performed to compare the bending actuation with the extensional actuation capability. The direct assembly method previously developed by the authors is used to fabricate ionic polymer transducers with controlled electrode dimensions and morphology. Electrodes with varying thickness are used to alter thickness of the active material. In the first experiment, the actuators are cut in beam shape and are allowed to bend in cantilever configuration. In the second configuration, bending is constrained by sandwiching the membranes between two solid metal plates and force is measured across the thickness of the actuator. A bimorph model is used to assess the effect of electrode thickness on the strain. An electromechanical coupling model presented by Leo et al. [1] determined the strain in the active areas as a function of the charge. This model is presented with a linear and a quadratic term that produces a 1st harmonic response for a sine wave actuation input. The quadratic term in the strain generates a zero net bending moment for ionic polymer transducers with symmetric electrodes. The linear term is also canceled in extensional actuation for symmetric electrodes. Experimental results demonstrates strain on the order of 110 μstrain in the thickness direction compared to 1700 μstrain peak to peak on the external fibers for the same transducer when it is allowed to bend under +/−2V potential at 0.5 Hz.
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Tsushima, Shohji, Fumiya Kondo, Sho Sasaki, and Shuichiro Hirai. "Efficient Utilization of the Electrodes in a Redox Flow Battery by Modifying Flow Field and Electrode Morphology." In The 15th International Heat Transfer Conference. Connecticut: Begellhouse, 2014. http://dx.doi.org/10.1615/ihtc15.ecs.009326.

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Reports on the topic "Morphology of electrojet"

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Landeros, J. Jr, P. Pizzo, M. Cantow, and F. Uribe. Investigation of the electronic properties and morphology of conducting polymer electrodes for engineering applications. Office of Scientific and Technical Information (OSTI), February 1995. http://dx.doi.org/10.2172/437778.

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Bedrov, Dmitry. Final Technical Report: SISGR: The Influence of Electrolyte Structure and Electrode Morphology on the Performance of Ionic-Liquid Based Supercapacitors: A Combined Experimental and Simulation Study. Office of Scientific and Technical Information (OSTI), August 2013. http://dx.doi.org/10.2172/1090143.

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