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Relevant bibliographies by topics / EPR; Optical spectroscopy

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Journal articles
Dissertations / Theses
Book chapters
Conference papers

Academic literature on the topic 'EPR; Optical spectroscopy'

Author: Grafiati

Published: 4 June 2021

Last updated: 16 February 2022

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Journal articles on the topic "EPR; Optical spectroscopy"

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Yamaga, M., H. Takeuchi, K. Holliday, P. Macfarlane, B. Henderson, Y. Inoue, and N. Kodama. "EPR and optical spectroscopy of Cr3+doped CaYAIO4." Radiation Effects and Defects in Solids 135, no. 1-4 (December 1995): 223–25. http://dx.doi.org/10.1080/10420159508229840.

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Burkov, V. I., S. V. Gudenko, and L. N. Alyabyeva. "Optical and EPR spectroscopy of a La3Ga5SiO14:Mn crystal." Journal of Experimental and Theoretical Physics 119, no. 4 (October 2014): 723–36. http://dx.doi.org/10.1134/s1063776114100148.

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Fedorov, V. V., T. Konak, J. Dashdorj, M. E. Zvanut, and S. B. Mirov. "Optical and EPR spectroscopy of Zn:Cr:ZnSe and Zn:Fe:ZnSe crystals." Optical Materials 37 (November 2014): 262–66. http://dx.doi.org/10.1016/j.optmat.2014.06.004.

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Falin, M. L., K. I. Gerasimov, A. M. Leushin, H. Bill, D. Lovy, and T. Sanadze. "EPR and optical spectroscopy of SrF2 doped with Yb3+." Journal of Alloys and Compounds 323-324 (July 2001): 692–95. http://dx.doi.org/10.1016/s0925-8388(01)01040-4.

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Gusev, V. A., A. P. Eliseev, E. G. Samoilova, V. P. Solntsev, and A. M. Yurkin. "Optical and EPR spectroscopy of chrysoberyl activated with nickel." Journal of Applied Spectroscopy 48, no. 5 (May 1988): 522–26. http://dx.doi.org/10.1007/bf00663466.

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SRINIVASU, CH, M. A. SAMI, A. EDUKONDALU, and SYED RAHMAN. "SYNTHESIS AND SPECTROSCOPY OF SOME QUATERNARY OXYFLUORIDE GLASSES DOPPED WITH COPPER." International Journal of Modern Physics: Conference Series 22 (January 2013): 284–91. http://dx.doi.org/10.1142/s2010194513010246.

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Electron paramagnetic resonance (EPR) and optical absorption spectra of copper ions in xLiF-(50-x)Li2O-20SrO-30Bi2O3 glass system have been studied. MDSC studies showed that the glass transition temperature decreases with LiF content. Optical absorption spectra of the pure glasses reveled that the cut off wave length increased and optical band gap energy decreased with increase in LiF content. EPR spectra of all the glass samples exhibit resonance signals characteristic of Cu2+ ions. The Cu2+ ions are in well-defined axial sites but subjected to small distortion leading to the broadening of the spectra. The spin-Hamiltonian parameter values indicate that the ground state of Cu2+ is d x2 y2 and the site symmetry around Cu2+ ions is tetragonally distorted octahedral. The optical absorption spectra exhibited a broad band corresponding to the d-d transition bands of Cu2+ ion. By correlating EPR and optical absorption data, the bond parameters are evaluated from various techniques.

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Mironova-Ulmane, N., A. I. Popov, A. Antuzevics, G. Krieke, E. Elsts, E. Vasil'chenko, I. Sildos, et al. "EPR and optical spectroscopy of neutron-irradiated Gd3Ga5O12 single crystals." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 480 (October 2020): 22–26. http://dx.doi.org/10.1016/j.nimb.2020.07.024.

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Falin, M. L., V. A. Latypov, B. N. Kazakov, A. M. Leushin, H. Bill, and D. Lovy. "EPR, ENDOR, and optical spectroscopy of the tetragonalYb3+center inKMgF3." Physical Review B 61, no. 14 (April 1, 2000): 9441–48. http://dx.doi.org/10.1103/physrevb.61.9441.

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Nosenko, A. E., R. E. Leshchuk, A. A. Sel’skii, and V. V. Kravchishin. "Optical and EPR spectroscopy of manganese ions in Sr3Ga2Ge4O14 crystals." Journal of Applied Spectroscopy 64, no. 6 (November 1997): 793–97. http://dx.doi.org/10.1007/bf02678862.

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Gaite, J. M., V. V. Izotov, S. I. Nikitin, and S. Y. Prosvirnin. "EPR and optical spectroscopy of impurities in two synthetic beryls." Applied Magnetic Resonance 20, no. 3 (April 2001): 307–15. http://dx.doi.org/10.1007/bf03162283.

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Dissertations / Theses on the topic "EPR; Optical spectroscopy"

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Twitchen, Daniel. "A study of defects and impurities in diamond." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389024.

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Sintyureva, Marina. "Engineering the phase behaviour of high performance inkjet colorants." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/engineering-the-phase-behaviour-of-high-performance-inkjet-colorants(0617f94f-7744-4576-9c05-69f659c52545).html.

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Dyes for inkjet printing are typically of the chromonic type. Chromonic mesophases have gained considerable attention as a well-defined group of lyotropic mesogens with different properties from conventional amphiphiles. While extensive research has been dedicated to the field of surfactant liquid crystals, structural and aggregation studies of chromonics have only emerged as a topic of interest within the last few years. The liquid crystalline structures in aqueous solutions of commercial Cu - phthalocyanine and black dyes have been examined using a combination of optical microscopy, UV-vis spectroscopy, nuclear magnetic resonance, wide- and small-angle X-ray diffraction and electronic paramagnetic resonance with a view to examining the phase behaviour of the chromonic mesophases formed over a broad range of concentrations and temperatures. These studies were performed in order to resolve outstanding problems concerning structural properties of these systems. Optical microscopy allowed us to identify the liquid crystalline phases and to construct the phase diagram. The observations show that both of these dyes form nematic mesophase above 15% wt / wt% dye. The small-angle diffraction data confirmed that the nematic phase for the black dye is maintained throughout the 16-25% composition range. A further increase in concentration leads to the formation of the hexagonal phase. The Cu – phthalocyanine dye also formed a nematic phase at low concentrations, with the aggregates undergoing a phase transition to an orientationally ordered chromonic liquid crystal phase at high dye concentration. These studies showed that this ordered phase possessed hexagonal symmetry. The wide-angle X-ray results demonstrated that aggregation involved π-π stacking of the molecules into columns. An additional reflection at ca. 6.8Å was observed for the black dye, which is believed to arise from “head – to – tail” packing of the molecules within the aggregates (a similar phenomenon observed in other azo dyes, e.g. Edicol Sunset Yellow).The densities of both dyes were measured over the studied range of concentrations. This enabled us to calculate the parameters of the aggregates within the hexagonal mesophase. A comparison between the area of the molecule and the cross-section of the aggregates showed that the aggregates of both dyes were the unimolecular stacks.

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Welinski, Sacha. "Propriétés optiques et magnétiques de cristaux dopés par des terres rares paramagnétiques pour les technologies quantiques." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEC001/document.

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Le développement considérable des signaux dans les bandes hyperfréquences (communications sans fil, radars, etc.) rend leur traitement extrêmement difficile. Il est en effet nécessaire d'analyser de larges bandes spectrales avec une grande résolution, ce que ne permettent pas les dispositifs purement électroniques. Une solution très prometteuse consiste à transposer les signaux hyperfréquences (hf) sur un laser puis à utiliser un cristal dopé par des ions de terres rares comme processeur. Cette technique tire parti des propriétés optiques exceptionnelles des ces matériaux, qui présentent des transitions à la fois extrêmement fines pour un centre unique (largeur homogène donnant la résolution spectrale) et larges pour un ensemble d'ions (largeur inhomogène donnant la bande d'analyse). Grâce à des techniques de pompage optique, ceci permet d'obtenir des bandes d'analyse de 20 GHz avec une résolution de 100 kHz, soit un rapport de 105. Ces résultats, obtenus dans des cristaux de Tm3+:Y3Al5O12, font l'objet d'études industrielles avancées, notamment en France par Thales, et auxquelles participe l'IRCP-MPOE. Le but du projet est de développer des cristaux dopés Er3+ pour une nouvelle génération d'analyseurs fonctionnant à 1.5 μm dans le but d'exploiter pleinement les technologies télécom en terme de transmission longue distance et de composants opto-électroniques. Les meilleurs cristaux actuels ne possèdent pas une largeur inhomogène suffisante pour l'application visée. Notre approche consistera à introduire un désordre chimique contrôlé, par exemple en utilisant un co-dopant, dans des monocristaux dopés Er3+ de haute qualité. Ceci permettra d'augmenter la largeur inhomogène optique mais pourrait aussi influencer la largeur homogène, point crucial pour l'analyse des signaux hf. Il s'agira de déterminer la nature et le niveau de désordre optimaux permettant d'obtenir les meilleures performances. D'une façon plus générale, ce travail permettra une compréhension approfondie des phénomènes dynamiques contrôlant la largeur homogène optique et de leur relation avec les structures cristallines. Outre l'analyse de signaux hyperfréquences, ceci pourra déboucher sur des avancées dans le traitement quantique de l'information dans le domaine télécom
Significant progresses have been made recently on radar communications. However it is still difficult to analyse radar communications both efficiently and on a large frequency span. This is due to the fact that pure electronic processors are not able to process rapidly signals with high bandwidths. A very promising solution consists in transposing radar signals on a optical carrier (laser) and process the signals via rare-earths-doped single-crystals, which are able to interact efficiently with light. Rare-earth-ion doped crystals can have very narrow optical transitions at liquid helium temperature, making them attractive for applications in quantum information processing and advanced RF signal processing. One key property of these materials is the potential for a high ratio between the optical inhomogeneous and homogeneous linewidths. This allows signals with high bandwidth to be stored in quantum memories for a long time, or alternatively, the high resolution spectral analysis of RF signals. Er3+ is particularly interesting because it has a transition at 1.5 mm that is directly compatible with telecommunication components in existing optical fiber networks. The aim of the project is to enhance the bandwidths of those atomic processors by introducing a chemical disorder in the single crystals doped with Er3+. This will lead to an inhomogeneous broadening of the optical transitions and could also reduce the optical homogeneous linewidths, and so, increase the processing bandwidth for radar signals. For that, a better understanding of the nature of the dynamical processes acting on the optical homogeneous linewidth is needed

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Schneider, Martin. "Návrh spektrometru s opticky detekovanou magnetickou rezonancí." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318818.

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Diplomová práce se zabývá návrhem a sestavením nového spektrometru opticky detekované magnetické rezonance (ODMR) modifikací stávajícího spektrometru magnetického kruhového dichroismu (MCD) přivedením mikrovlnného ozařování. Je navrhnut nový držák vzorku umožnující osvětlení jak viditelným světlem, tak mikrovlnným zářením. Pro přivedení vlnění o nižších frekvencích je navržena anténa, určená k umístění pod vzorkem. Schopnosti celého systému jsou demonstrovány na sloučenínách kovových komplexů.

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Martínek, Tomáš. "Návrh nerezonančního držáku vzorku pro obecné použití v terahertzové elektronové spinové resonanční spektroskopii." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-382623.

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Cílem diplomové práce je navrhnout konstrukční řešení držáků vzorků pro vysokofrekvenční elektron paramagnetickou resonanci. Předmětem návrhu je vytvořit jednoduchý zamykací systém pro spojování mikrovlnného vlnovodu a držáku vzorku. Dále navrhnout systém s řešením držáku pro více vzorků. Toto unikátní provedení držáku povede k několikanásobné úspoře celkového času měření vzorků. Poslední návrh spočívá v optimalizaci držáku vzorku s možností naklápění osy, kterou lze díky přímému napojení na piezoelektrický rotátor pootáčet s přesností na miliradiány. Oba typy držáku vzorku jsou navrženy s ohledem na automatizaci měření.

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Gacem, Lakhdar. "Cristallogenèse et caractérisations du diphosphate Na2ZnP2O7 pur et dopé et de la solution solide de type pérovskite Na(1x)BaxNb(1x)TixO3." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2010. http://tel.archives-ouvertes.fr/tel-00474354.

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Les propriétés physiques d'un matériau sont intimement liées à sa structure cristalline et dans le cas d'ions dopants aux sites qu'ils occupent. La première partie de ce travail est dédiée au matériau diphosphate de sodium et de zinc Na2ZnP2O7, cristallisé out vitreux et ceci pour les ions dopants Co2+, Ni2+, Mn2+ et Eu3+. Les phases cristallisées ont été obtenues par la méthode Czochralski, les verres par trempe à partir de l'état fondu. Un ensemble de caractéristiques physiques ont été mises en jeu (Raman, infrarouge, RPE, absorption optique, luminescence) pour déterminer les sites occupés par les ions dopants et l'influence sur les propriétés optiques. La deuxième partie de cet travail consiste à une meilleure connaissance des matériaux diélectriques sans plomb appartenant à la famille pérovskite et plus particulièrement à la solution solide NaNbO3-BaTiO3. Des monocistaux ont été obtenus par la méthode des flux et caractérisés en utilisant plusieurs techniques : diffraction X, microanalyse, évolution thermique des domaines ferroélectriques-ferroélastiques, mesures diélectriques, piézoélectriques et pyroélectriques.

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Teeling-Smith, Richelle Marie. "Single Molecule Electron Paramagnetic Resonance and Other Sensing and Imaging Applications with Nitrogen-Vacancy Nanodiamond." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1424779811.

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Günther, Marcus. "Harte amorphe wasserstoffhaltige Kohlenstoffschichten mittels mittelfrequenzgepulster Plasmaentladungen." Doctoral thesis, Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-95197.

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Harte amorphe wasserstoffhaltige Kohlenstoffschichten (a-C:H) haben in den letzten Jahrzehnten stark an Bedeutung gewonnen. Diese Art von Hartstoffschichten wird zunehmend für die Reduzierung von Reibung und Verschleiß in unterschiedlichen Bereichen eingesetzt. In der Forschung, aber auch für Kleinserien, werden a-C:H-Schichten üblicherweise mit Hochfrequenzplasmaentladungen abgeschieden. Eine Alternative ist die Plasmaaktivierung mit einer asymmetrisch bipolar gepulsten Spannung im Mittelfrequenzbereich. Auf diese Weise wird eine homogene Beschichtung großer Substratflächen mit qualitativ hochwertigen Schichten ermöglicht. Die vorliegende Arbeit beschäftigt sich mit der plasmagestützten Abscheidung von harten a-C:H-Schichten mit mittelfrequenzgepulsten Entladungen. Zur Schichtabscheidung werden Ethin-Argon- und Isobuten-Argon-Gasgemische verwendet. Der Einfluss des Prozessdrucks auf den Abscheideprozess und die Schichteigenschaften wird untersucht. Dazu wurden Argonentladungen und Beschichtungsplasmen mittels optischer Emissionsspektroskopie charakterisiert. Zur Charakterisierung der Schichteigenschaften wurden unter anderem Nanoindentation-Messungen, elastische Rückstreudetektionsanalysen und thermische Desorptionsspektroskopie verwendet. Zur Untersuchung des Einflusses der Ionen auf das Schichtwachstum wird ein Modell zur Identifizierung von Ionenspezies in Beschichtungsplasmen vorgestellt. In Verbindung mit der Messung der Substratströme konnte der Ionenanteil am Schichtwachstum bestimmt werden. Ein weiterer Teil der vorliegenden Arbeit untersucht ein Hybridverfahren, in dem die mittelfrequenzgepulste Entladung mit einer zusätzlichen ECR-Entladung kombiniert wird. Es wird gezeigt, dass durch dieses Hybridverfahren eine deutliche Steigerung der Abscheiderate harter a-C:H-Schichten erreicht werden kann. Die abgeschiedenen Schichten wurden zusätzlich bezüglich ihrer Oberflächenstruktur und ihrer Verschleißfestigkeit untersucht.

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Rüdiger, Andreas. "Light induced charge transfer processes and pyroelectric luminescence in Sn2P2S6." Doctoral thesis, 2006. https://repositorium.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-2001092814.

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Sn2P2S6 is ferroelectric at room temperature. It is of technological interest in a variety of applications such as pyroelectric motion detectors and the photorefractive effect. Until now the defect structure and the light-induced charge transfer processes in this material have not been subject of a detailed investigation. The main part of this thesis describes and interprets data of electron paramagnetic resonance (EPR), optical absorption spectroscopy and their combination at 10 K to unravel the light-induced sensitization and charge transfer paths. In the photosensitized crystal at excitation with 1.5 eV a hole is transferred from a previously generated Sn3(plus) site to another inequivalent site of the ferroelectric phase. For higher excitation energies another hole present as Fe3(plus) is transferred to S2- creating S-. Optical absorption spectroscopy at room temperature indicates the validity of this model for evelated temperature below the Curie-temperature as well. It is consistent with both our interpretation of EPR spectra and the observation of photoinduced persistent conductivity that electronic bipolarons are the negative charge carriers. An additional chapter interprets a manifestation of pyroelectric luminescence already reported in other pyroelectric materials in terms of an internal Poole-Frenkel-effect induced by the pyroelectric field under changing temperature. The numerical simulation based on published material parameters is in good agreement with the experimental data for both heating and cooling.

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Scrutton, Philip. "Optical spectroscopy of intact and intermixed gallium arsenide/aluminum arsenide superlattice structures." 2006. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=450413&T=F.

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Book chapters on the topic "EPR; Optical spectroscopy"

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Reddy, B. J., Jun Yamauchi, Y. P. Reddy, A. V. Chandrasekhar, and R. V. S. S. N. Ravikumar. "EPR and optical absorption spectroscopy on minerals." In EPR in the 21st Century, 575–84. Elsevier, 2002. http://dx.doi.org/10.1016/b978-044450973-4/50095-0.

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Kohmoto, T., Y. Fukuda, and M. Kunitomo. "Fourier‐transform ESR spectroscopy and observation of ultrafast spin‐lattice relaxation by optical means." In EPR in the 21st Century, 700–705. Elsevier, 2002. http://dx.doi.org/10.1016/b978-044450973-4/50114-1.

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Malchukova, Eugenia. "Influence of the Doping Ion Nature and Content on Defect Creation Processes under the Effect of Ionizing Radiation in Aluminoborosilicate Glasses." In Recent Techniques and Applications in Ionizing Radiation Research. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.92317.

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Effects of ionizing irradiation on defect creation processes have been studied in rare earth (RE)-doped (RE = Sm, Gd, Eu, Ce, Nd) aluminoborosilicate glass with use of the electron paramagnetic resonance (EPR) and optical spectroscopy. As a function of RE ion nature, we observe that doping significantly influences the nature of the defects produced during irradiation and more specifically the relative proportions between hole and electron defect centers. Strong decrease of defect production efficiency under ionizing radiation independence on both the RE doping content and on the relative stability of the RE different oxidation states is also clearly revealed. The results could be explained by dynamical reversible trapping of the electron-hole pairs produced during irradiation on the different RE charge states as well as by RE segregation and pre-existing defects speciation in ABS glass structure.

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Herz, Norman, and Ervan G. Garrison. "Instrumental Analytical Techniques." In Geological Methods for Archaeology. Oxford University Press, 1998. http://dx.doi.org/10.1093/oso/9780195090246.003.0017.

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Instrumental analysis has become a mainstay in the study of provenance of artifacts and their materials. A veritable "alphabet soup" of acronyms shorten the often ponderous names of the large number of techniques available today: XRF (x-ray fluorescence), XRD (x-ray diffraction), NAA (neutron activation analysis), AAS (atomic absorption spectroscopy), PIXE (proton-induced x-ray emission), ICP (inductively coupled plasma spectroscopy), FTTR (Fourier transform infrared spectroscopy), EMP (electron microprobe), RIS (resonance ionization spectroscopy), ESR (electron spin resonance), CL (cathodoluminescence spectroscopy), STM (scanning tunneling microscopy), AFM (atomic force microscopy), NSOM (near-field scanning optical microscopy), and SEM/TEM (scanning/transmission electron microscopy).

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Conference papers on the topic "EPR; Optical spectroscopy"

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Padlyak, B. V., V. O. Protsiuk, I. I. Kindrat, A. Drzewiecki, V. T. Adamiv, Ya V. Burak, and I. M. Teslyuk. "EPR and optical spectroscopy of the V-doped borate glasses." In 2014 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE). IEEE, 2014. http://dx.doi.org/10.1109/omee.2014.6912373.

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Whitmore, Michael H., Christian T. Farrar, David J. Singel, Bart Buysse, Jan Coremans, and Jan Schmidt. "Characterization of Optical Centers in Mn:Ba3(VO4)2 by Spin-Echo EPR Spectroscopy." In Advanced Solid State Lasers. Washington, D.C.: OSA, 2004. http://dx.doi.org/10.1364/assl.1994.ts3.

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Baumgarten, M., and L. Gherghel. "Redox states of C/sub 60/ and C/sub 70/ measured by EPR and optical absorption spectroscopy." In International Conference on Science and Technology of Synthetic Metals. IEEE, 1994. http://dx.doi.org/10.1109/stsm.1994.835006.

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Ruediger, A., O. F. Schirmer, A. Kadashchuk, and A. Grabar. "Light-induced charge transfer in nominally pure and iron doped Sn2P2S6: a study by combined EPR-optical absorption spectroscopy." In Photorefractive Effects, Materials, and Devices. Washington, D.C.: OSA, 2001. http://dx.doi.org/10.1364/pemd.2001.568.

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Zimmer, J., D. Nielsen, T. A. Anderson, M. Schade, N. Saha, and G. Thome. "Characterization and Elimination of Forward Snapback Defects in GaAs Light Emitting Diodes." In ISTFA 1996. ASM International, 1996. http://dx.doi.org/10.31399/asm.cp.istfa1996p0239.

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Abstract The p-n junction of a GaAs light emitting diode is fabricated using liquid phase epitaxy (LPE). The junction is grown on a Si doped (~1018/cm3) GaAs substrate. Intermittent yield loss due to forward voltage snapback was observed. Historically, out of specification forward voltage (Vf) parameters have been correlated to abnormalities in the junction formation. Scanning electron (SEM) and optical microscopy of cleaved and stained samples revealed a continuous layer of material approximately 2.5 to 3.0 urn thick at the n-epi/substrate interface. Characterization of a defective wafer via secondary ion mass spectroscopy (SIMS) revealed an elevated concentration of O throughout the region containing the defect. X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES) data taken from a wafer prior to growth of the epi layers did not reveal any unusual oxidation or contamination. Extensive review of the processing data suggested LPE furnace pressure was the obvious source of variability. Processing wafers through the LPE furnace with a slight positive H2 gas pressure has greatly reduced the occurrence of this defect.

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Ma, Tao, Heng Liu, and Yuying Xiong. "Study of Optical Emission Spectroscopy in a GaN ECR-PECVD." In 2010 Symposium on Photonics and Optoelectronics (SOPO 2010). IEEE, 2010. http://dx.doi.org/10.1109/sopo.2010.5504258.

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Galyametdinov, Yuiriy, Dmitriy Sagdeev, Andrey Sukhanov, Violeta Voronkova, and Radik Shamilov. "Monitoring of Mn ions incorporation into quantum dots by EPR and luminescence spectroscopy." In IV International Conference on Applications of Optics and Photonics, edited by Manuel Filipe P. Martins Costa. SPIE, 2019. http://dx.doi.org/10.1117/12.2530906.

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Chai, Rukaun, Yuetian Liu, Qianjun Liu, Xuan He, and Pingtian Fan. "Effect and Mechanism of CO2 Electrochemical Reduction for CCUS-EOR." In SPE Annual Technical Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/206135-ms.

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Abstract Unconventional reservoir plays an increasingly important role in the world energy system, but its recovery is always quite low. Therefore, the economic and effective enhanced oil recovery (EOR) technology is urgently required. Moreover, with the aggravation of greenhouse effect, carbon neutrality has become the human consensus. How to sequestrate CO2 more economically and effectively has aroused wide concerns. Carbon Capture, Utilization and Storage (CCUS)-EOR is a win-win technology, which can not only enhance oil recovery but also increase CO2 sequestration efficiency. However, current CCUS-EOR technologies usually face serious gas channeling which finally result in the poor performance on both EOR and CCUS. This study introduced CO2 electrochemical conversion into CCUS-EOR, which successively combines CO2 electrochemical reduction and crude oil electrocatalytic cracking both achieves EOR and CCUS. In this study, multiscale experiments were conducted to study the effect and mechanism of CO2 electrochemical reduction for CCUS-EOR. Firstly, the catalyst and catalytic electrode were synthetized and then were characterized by using scanning electron microscope (SEM) & energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). Then, electrolysis experiment & liquid-state nuclear magnetic resonance (1H NMR) experiments were implemented to study the mechanism of CO2 electrochemical reduction. And electrolysis experiment & gas chromatography (GC) & viscosity & density experiments were used to investigate the mechanism of crude oil electrocatalytic cracking. Finally, contact angle and coreflooding experiments were respectively conducted to study the effect of the proposed technology on wettability and CCUS-EOR. SEM & EDS & XPS results confirmed that the high pure SnO2 nanoparticles with the hierarchical, porous structure, and the large surface area were synthetized. Electrolysis & 1H NMR experiment showed that CO2 has converted into formate with the catalysis of SnO2 nanoparticles. Electrolysis & GC & Density & Viscosity experiments indicated that the crude oil was electrocatalytically cracked into the light components (<C20) from the heavy components (C21∼C37). As voltage increases from 2.0V to 7.0V, the intensity of CO2 electrocchemical reduction and crude oil electrocatalytic cracking enhances to maximum at 3.5V (i.e., formate concentration reaches 6.45mmol/L and carbon peak decreases from C17 to C15) and then weakens. Contact angle results indicated that CO2 electrochemical reduction and crude oil electocatalytic cracking work jointly to promote wettability alteration. Thereof, CO2 electrochemical reduction effect is dominant. Coreflooding results indicated that CO2 electrochemical reduction technology has great potential on EOR and CCUS. With the SnO2 catalytic electrode at optimal voltage (3.5V), the additional recovery reaches 9.2% and CO2 sequestration efficiency is as high as 72.07%. This paper introduced CO2 electrochemical conversion into CCUS-EOR, which successfully combines CO2 electrochemical reduction and crude oil electrocatalytic cracking into one technology. It shows great potential on CCUS-EOR and more studies are required to reveal its in-depth mechanisms.

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Wu, W. B., S. X. Peng, H. T. Ren, Y. Xu, J. M. Wen, A. L. Zhang, T. Zhang, et al. "Optical emission spectroscopy for plasma diagnosis of 2.45 GHz ECR ion source at Peking University." In Proceedings of the 17th International Conference on Ion Sources. Author(s), 2018. http://dx.doi.org/10.1063/1.5053246.

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Popov, Alexey P., Jürgen Lademann, Alexander V. Priezzhev, and Risto Myllylä. "Reconstruction of stratum corneum profile of porcine ear skin after tape stripping using UV/VIS spectroscopy." In European Conference on Biomedical Optics. Washington, D.C.: OSA, 2007. http://dx.doi.org/10.1364/ecbo.2007.6628_70.

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