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Stability of FeVO4-II under Pressure: A First-Principles Study

PRICILA BETBIRAI ROMERO VAZQUEZ SINHUE LOPEZ MORENO Daniel Errandonea (2022, [Artículo])

"In this work, we report first-principles calculations to study FeVO4 in the CrVO4-type (phase II) structure under pressure. Total-energy calculations were performed in order to analyze the structural parameters, the electronic, elastic, mechanical, and vibrational properties of FeVO4-II up to 9.6 GPa for the first time. We found a good agreement in the structural parameters with the experimental results available in the literature. The electronic structure analysis was complemented with results obtained from the Laplacian of the charge density at the bond critical points within the Quantum Theory of Atoms in Molecules methodology. Our findings from the elastic, mechanic, and vibrational properties were correlated to determine the elastic and dynamic stability of FeVO4-II under pressure. Calculations suggest that beyond the maximum pressure covered by our study, this phase could undergo a phase transition to a wolframite-type structure, such as in CrVO4 and InVO4."

FeVO4 under pressure CrVO4-type structure First-principles Mechanical properties Vibrational properties Electronic properties CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA FÍSICA DEL ESTADO SÓLIDO CRISTALOGRAFÍA CRISTALOGRAFÍA

GENERATION OF LG VECTOR MODES WITH ULTRAHIGH STABILITY BASED ON COMPLEX AMPLITUDE MODULATION IN AN ON-AXIS CONFIGURATION

Gloria Elizabth Rodríguez García (2023, [Tesis de maestría])

"This thesis presents a novel technique for generating vector beams using complex amplitude modulation (CAM) in an on-axis configuration. The holograms used to generate the beams were created using the Mathlab software and displayed on a reflective spatial light modulator (SLM). The main goal of this research was to address both the purity and stability of the beams during generation and propagation, introducing a quantitative approach to assess their stability. As a proof-of-concept, Laguerre-Gaussian vector beams have been generated and characterized using Stokes polarimetry with the proposed experimental set up."

Structured light Laguerre-Gauss vector beams Stokes polarimetry Beam generation Spatial light modulators CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA OPTICA FÍSICA OPTICA FÍSICA

EFFICIENT FLUORESCENT AND PHOSPHORESCENT OLEDs BY SPIN COATING TECHNIQUE AND A NEW ANODE BASED ON CONDUCTIVE PEDOT:PSS

Luis Abraham Lozano Hernández (2020, [Tesis de doctorado])

"Fluorescent and phosphorescent Organic Light Emitting Diode (OLED) devices were fabricated by solution process and optimized. From their basic characterization (J-V-L curves, electroluminescence spectra) external quantum efficiency (EQE) was calculated. Two small molecule, carbazole derivatives (CZ-1 and CZ-2), previously reported and used for OLEDs showed very good luminances (~ 4000 cd/m2) and current densities (< 200 mA/cm2) resulting in a high EQE (9.5 %). Likewise, fluorescent OLEDs based in the new polymer PF-2F presented an acceptable performance even on a simple architecture with a good EQE (2.6 %), photoluminescence quantum yield (PLQY) about 1 and excellent properties of processability. The influence of its CF3 group in the optical, chemical, electronic and mechanical properties in OLEDs was determined.

Also, a new family of three fluorescent oligomers (BT-F32, BT-F42 and BT-F52) with excellent properties in solution, high PLQY (~1) and highly luminescent, were used in simple and multilayer OLEDs achieving a very high luminance (29 499 cd/m2). These oligomers have different chain lengths, which influence the device luminance, efficiency and their lifetime. Lifetime was monitored and the stretched exponential decay (SED) model was used in order to obtain the device half-life (LT50). Also, phosphorescent devices, based on a host/guest system (PVK:Ir(ppy)3), were prepared, the influence of the electron transport layer (ETL) into the electron/hole ratio was analyzed.

By using a new proposed method, a PEDOT:PSS anode was developed and applied in rigid and flexible substrates, with low sheet resistance (40 Ω/□) and acceptable transmittance (> 85%). This new proposed method consists in volume evaporation, in which basically the loss of water induces closeness among the conductive fractions of PEDOT. This PEDOT:PSS anode easy of fabricating following an economical procedure could be applied not just in OLEDs but in other optoelectronic devices such as organic photovoltaic cells (OPVs), perovskite solar cells (PeSCs), etc."

OLEDs Fluorescence Phosphorescence PEDOT:PSS Polymer Anode INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA ELECTRÓNICA DISPOSITIVOS SEMICONDUCTORES DISPOSITIVOS SEMICONDUCTORES

Servicios digitales públicos: el IMPI y la emisión de títulos de patente que realiza

Pamela Serrano Magaña (2023, [Otro, Trabajo de grado, maestría])

Las Tecnologías de la Información y Comunicación (TIC) han logrado acercar a la población a contenidos y formas de intercambio de información que anteriormente no eran posibles; el Internet ha derrumbado fronteras entre las sociedades, los gobiernos, el conocimiento y las oportunidades, creando a su vez nuevas necesidades para caer en el círculo virtuoso de la innovación.

Este artículo plantea una transformación integral en una etapa digital específica dentro de los procesos internos del IMPI, desde el expediente físico hacia el expediente digital para automatizar los procesos de emisión de títulos de concesión de patentes de invención lo que resultaría en una reducción del índice de errores humanos involuntarios, así como la mejora en la atención a los usuarios, al ofrecer mayor certeza en los servicios proporcionados y mayor seguridad en el tratamiento de su información, así como un apego a las normas jurídicas aplicables. El objetivo de esta implementación es reducir el índice de equivocaciones en la documentación oficial emitida disminuyendo en consecuencia, los retrasos y las incidencias fortuitas, y para dicho fin se proponen dos soluciones. La primera, el desarrollar un nuevo módulo dentro del sistema principal existente, que permitirá exportar los datos y generar el título directamente en el formato requerido. La segunda, es la utilización de tecnología de automatización robótica de procesos o RPA por sus siglas en inglés (Robotic Process Automation) para hacer uso de una herramienta que sustituya a la transcripción manual por una transcripción automática.

Digitalización Servicios digitales Gobierno electrónico Instituto Mexicano de la Propiedad Industrial INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS CIENCIAS TECNOLÓGICAS