On the role of triethylene glycol in the preparation of highly active Ni-Mo/Al2O3 hydrodesulfurization catalysts: A spectroscopic study

The interaction of triethylene glycol (TEG) with alumina and its role in preparing improved NiMo/Al2O3 hydrodesulfurization catalysts was investigated by spectroscopic methods. The FT-IR study shows that TEG is mainly adsorbed on the corners and edges of the alumina microcrystals where the strongest Lewis sites and the higher OH frequency hydroxyl groups are mainly located. It is also observed that the Mo O stretching vibration of surface molybdenyl groups in the oxide catalyst precursor is shifted down in the presence of TEG, indicating a lower interaction with the alumina surface. The IR spectra of CO adsorbed on the reduced/sulfided NiMo/Al2O3 catalysts confirm that the amount of promoted phase (NiMoS sites) increases in the samples prepared with TEG. Accordingly, the activity measurements in the HDS of 4,6-dimethyldibenzothiophene show that the catalyst prepared with TEG is more active than the one prepared without it. It is proposed that TEG and its decomposition products, formed upon heating (mainly acetates) occupy preferably the strongly interacting edge and corner sites of the alumina crystals, forcing the Mo and Ni species to migrate mainly to the less reactive plane faces. This weakens the metalsupport interaction allowing a better sulfidation and, at the same time, favoring the Ni\u2013Mo interaction and the formation of the promoted NiMoS phase

Desarrollo de herramientas de búsqueda en los archivos históricos de la CompañÍa de Jesús

El trabajo de los historiadores es pesado y difícil ya que consiste, fundamentalmente, en la localización, análisis e interpretación de documentos antiguos. Estos documentos, cuando están disponibles para su consulta, deben ser leídos uno por uno y todas las posibles referencias cruzadas, revisadas una por una. La Compañía de Jesús llegó a la Nueva España en el siglo XV y trabajó en colegios, misiones, parroquias y hospitales a lo largo de todo el continente hasta la expulsión de la Orden en 1767. Durante este tiempo, la Compañía de Jesús puso en marcha un sistema de comunicación conocido como las Cartas Anuales o Cartas Annuas que el Provincial enviaba al General de la Compañía en Roma. Cada una de las Cartas Anuales relataba las actividades llevadas a cabo por miembros de la Compañía. Para ayudarse a redactar cada Carta y con el fin de circular la información en toda la Provincia de la Nueva España, cada uno de los encargados de las obras enviaba al Provincial una o varias cartas conocidas como Puntos de Annua. La Compañía de Jesús, junto con el Archivo General de la Nación y el Instituto Nacional de Antropología e Historia se dio a la tarea de recopilar todas las Cartas Anuales escritas desde que los jesuitas llegaron a la Nueva España hasta su expulsión en 1767. Esta búsqueda resultó en más de 13000 folios que debieron paleografiarse para ayudar a la investigación histórica sobre la Compañía de Jesús. Como resultado de este trabajo de recuperación y paleografía y para facilitar el acceso y manejo de los documentos, se decidió crear una herramienta informática que ofreciera a los investigadores un motor de búsqueda para hacer referencias cruzadas rápida y fácilmente, así como el acceso a los documentos a través de índices temáticos. El desarrollo de esta herramienta presentó varios problemas técnicos que se han ido solucionando. Por ejemplo, la necesidad de que los documentos en formato electrónico siguieran fielmente las reglas de la paleografía. Este requerimiento hizo necesaria la realización de un filtro para manipular los archivos en formato XML. Se desarrolló también la interfaz gráfica para acceder a los índices temáticos y el motor de búsqueda para realizar referencias cruzadas en una o varias palabras, continuas o discontinuas en el texto del documento. La herramienta ha sido bien recibida por los investigadores y se ha decido aumentarla con algoritmos de Text-Mining para aumentar las capacidades de la búsqueda así como la generación de referencias cruzadas entre los documentos.ITESO, A.C

Scientific culture through Final Thesis in bachelor degree

Resúmenes IV Congreso VetDoc de Docencia Veterinaria, León 2017 (6-7 de Julio)[ES] Durante el curso 2015-16 se ha llevado a cabo una experiencia innovadora en la Facultad de Veterinaria de la Universidad de Zaragoza consistente en la realización de dos Trabajos Fin de Grado (TFG) que, manteniendo su objetivo y carácter académico, han contribuido además a difundir las líneas de investigación sobre las que se trabaja en la Facultad, mediante sendos blogs temáticos desarrollados específicamente y de forma complementaria, dentro del ámbito de la divulgación científica

New contributions to the geographical distinction of painted andalusi plinths

[EN] Few examples remain of artistic Andalusi decoration in the form of painted plinths in residential settings. Several technological issues have arisen when noting potential connections in an attempt to contextualize the styles, geography and chronologies of these plinths. Using XRD, FTIR and stratigraphic analysis, and considering previous research, the study of execution techniques and materials observed in plinths in Baŷŷāna (Almería) has made it possible to establish parallels with decorated plinths from the Barrio de casas de la Alcazaba in Malaga. Based on these results, interesting conclusions can be drawn regarding production techniques which are in keeping with the survival of certain execution procedures of Roman origin for renderings. Furthermore, the existence of a production nucleus grouping the examples from Almería and Malaga is proposed within a technical context which would set them apart.[ES] Una manifestación artística de la decoración andalusí de la que se conservan escasos testimonios son los zócalos pintados en el ámbito doméstico. Los intentos por contextualizar estilística, geográfica y cronológicamente estos zócalos han planteado algunas cuestiones de índole tecnológica a la hora de apuntar posibles conexiones. El estudio de las técnicas de ejecución y materiales empleados en zócalos de Baŷŷāna (Almería), mediante análisis estratigráfico, DRX y FTIR, ha permitido establecer paralelismos con zócalos decorados procedentes del barrio de casas de la Alcazaba de Málaga a partir de una investigación anterior. Los resultados permiten extraer interesantes conclusiones sobre las técnicas de elaboración, que son congruentes con la pervivencia de algunos procedimientos de ejecución de los enlucidos de raigambre romana. Además, se plantea aquí la existencia de un núcleo de producción que agruparía los ejemplos provenientes de Almería y Málaga, cuyo contexto técnico los diferenciaría.Alejandre Sánchez, FJ.; Núñez Guerrero, C.; Díaz Ramos, S.; Pérez-Malumbres Landa, A. (2023). Nuevas aportaciones a la diferenciación geográfica de los zócalos pintados andalusíes. Loggia, Arquitectura & Restauración. (36):40-51. https://doi.org/10.4995/loggia.2023.1996940513

Geochemical study of products associated with spontaneous oxidation of coal in the Cerro Pelado Formation, Venezuela

The aim of this research work is a geochemical, mineralogical, and textural characterization of spontaneously smouldered coal-derived products in northwestern Venezuela (Cerro Pelado Formation, some 10 km from Pedregal city). Several solid samples were collected from this formation, six of unweathering coal, an other six of resulting unmelted rocks forming on a surface coal bed, and the last four of mineralizations found accumulating around gas vents. The fresh coal and the unmelted material were analysed by scanning electron microscopy, X-ray diffraction, and proximate techniques. Products such as magnetite and chabazite-K were identified in the alteration rocks. Likewise, both materials were also studied in order to determine the mobilization of 17 elements into the environment; such elements were analysed through inductively coupled plasma atomic emission spectroscopy on extracts obtained by a sequential extraction method: each sample was firstly extracted with MilliQ water and then the resultant residue was washed. This and the subsequently resulting residues are extracted according to the mentioned procedure by using, respectively, ammonium acetate, chlorhydric acid, peroxide and chlorhydric acid, nitric acid and fluorhydric acid, and nitric acid. The studied elements are classified as highly mobile (Na, Ni, ...), nearly immobile (Ti, P) and partially mobile (Mg, Fe, K,...). In regards to mineralizations around fumaroles associated with smoldering coal seams, Fourier-transform infrared spectroscopy and X-ray diffraction analyses have revealed the presence of salammoniac, mascagnite and other solid combustion compounds formed by reaction of gas emitted from coal oxidation, in addition to previously non-reported sulfur-rich by-products associated with gas fissures, particularly ammonium thiosulfate, a phase first obtained only synthetically in the laboratory. Another objective of the research was to collect and analyse gases escaping from surficial vents. Relatively high concentrations of several aromatic compounds were detected in the gas collected at the studied coal outcrop, as well as aliphatic hydrocarbons including ethane, propane, butanes, among others. High contents of carbon monoxide, methane and carbon dioxide were also measured for gas samples

Age norms for grating acuity and contrast sensitivity in children using eye tracking technology

Key messages: Visual acuity is the most used method to assess visual function in children. Contrast sensitivity complements the information provided for visual acuity, but it is not commonly used in clinical practice. Digital devices are increasingly used as a method to evaluate visual function, due to multiple advantages. Testing with these devices can improve the evaluation of visual development in children from a few months of age. Visual acuity and contrast sensitivity tests, using eye tracking technology, are able to measure visual function in children across a wide range of ages, objectively, quickly and without need of an experienced examiner. Purpose: To report age-normative values for grating visual acuity and contrast sensitivity in healthy children using a digital device with eye tracking technology and to validate the grating acuity test. Methods: In the first project of the study, we examined healthy children aged between 6 months and 7 years with normal ophthalmological assessment. Grating visual acuity (VA) and contrast sensitivity (CS) were assessed using a preferential gaze paradigm with a DIVE (Device for an Integral Visual Examination) assisted with eye tracking technology to provide age norms. For the validation project, we compared LEA grating test (LGT) with DIVE VA in a group of children aged between 6 months and 4 years with normal and abnormal visual development. Results: Fifty-seven children (2.86 ± 1.55 years) were examined with DIVE VA test and 44 successfully completed DIVE CS test (3.06 ± 1.41 years). Both, VA and CS values increased with age, mainly along the first two years of life. Sixty-nine patients (1.34 ± 0.61 years) were included in the DIVE VA test validation. The mean difference between LGT and DIVE VA was − 1.05 ± 4.54 cpd with 95% limits of agreement (LoA) of − 9.95–7.84 cpd. Agreement between the two tests was higher in children younger than 1 year with a mean difference of − 0.19 ± 4.02 cpd. Conclusions: DIVE is an automatic, objective and reliable tool to assess several visual function parameters in children, and it has good agreement with classical VA tests, especially for the first stage of life

Sylow permutable subnormal subgroups of finite groups

Paper published by Elsevier in J. Algebra, 215(2):727-738 (2002). The final publication is available at www.sciencedirect.com. http://dx.doi.org/10.1006/jabr.2001.9138[EN] An extension of the well-known Frobenius criterion of p-nilpotence in groups with modular Sylow p-subgroups is proved in the paper. This result is useful to get information about the classes of groups in which every subnormal subgroup is permutable and Sylow permutable.Supported by Proyecto PB97-0674 and Proyecto PB97-0604-C02-02 from DGICYT, Ministerio de Educaci´on y CienciaBallester Bolinches, A.; Esteban Romero, R. (2002). Sylow permutable subnormal subgroups of finite groups. Journal of Algebra. 2(251). doi:10.1006/jabr.2001.9138225

Sylow permutable subnormal subgroups of finite groups II

Paper published in http://journals.cambridge.org/abstract_S0004972700019948[EN] In this paper a local version of Agrawal's theorem about the structure of finite groups in which Sylow permutability is transitive is given. The result is used to obtain new characterisations of this class of finite groups.Supported by Proyecto PB97-0674-C02-02 and Proyecto PB97-0604 from DGICYT, Ministerio de Educaci´on y Cienciahttp://journals.cambridge.org/abstract_S0004972700019948Ballester Bolinches, A.; Esteban Romero, R. (2001). Sylow permutable subnormal subgroups of finite groups II. Bulletin of the Australian Mathematical Society. 64. doi:10.1017/S00049727000199486

Phosphogypsum waste lime as a promising substitute of commercial limes : a rheological approach

This paper presents the rheological properties of three types of lime putty, specifying the influence of their origin. The study aims to compare a special lime putty prepared from phosphogypsum with a commercial lime powder and an aged lime putty. The results obtained in terms of chemical composition, crystalline structure, grain size and rheological characterization, (linear viscoelasticity, shear rate and time-dependent flow behaviour) are presented in the study. Putties studied present a similar rheological response, which mainly depends on the particle size and water content. Lower values of the linear viscoelastic functions and viscosity were found for the phosphogypsum lime putty, in agreement with the higher particle size. Transient flow tests reveal a predominant elastic response with no significant shear-induced structural perturbations. However, either a thickening phenomenon over time, i.e. rheopexy, favoured at low shear rates, or a viscosity decrease, i.e. thixotropy, favoured at high shear rates, was observed.The authors would like to thank the aid of CITIUS at the University of Seville for the use of their laboratories for the characterization analyses. A.M.B.-L. has received a Ph.D. Research Grant from the Ministerio de Education, Cultura y Deporte (FPU16/03697)

Phosphogypsum waste lime as a promising substitute of commercial limes: A rheological approach

This paper presents the rheological properties of three types of lime putty, specifying the influence of their origin. The study aims to compare a special lime putty prepared from phosphogypsum with a commercial lime powder and an aged lime putty. The results obtained in terms of chemical composition, crystalline structure, grain size and rheological characterization, (linear viscoelasticity, shear rate and time-dependent flow behaviour) are presented in the study. Putties studied present a similar rheological response, which mainly depends on the particle size and water content. Lower values of the linear viscoelastic functions and viscosity were found for the phosphogypsum lime putty, in agreement with the higher particle size. Transient flow tests reveal a predominant elastic response with no significant shear-induced structural perturbations. However, either a thickening phenomenon over time, i.e. rheopexy, favoured at low shear rates, or a viscosity decrease, i.e. thixotropy, favoured at high shear rates, was observed