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In the present work, the manufacture of a Cu-9Al-3Ag alloy was carried out easily through a green molding process. After dimensioning and slitting, the alloy samples were subjected to quenching, normalizing, and annealing heat treatments, to exert phase transformations that would, in return, aid into clarifying the influence of the phases present on the mechanical properties, such as hardness, as well as the behavior when exposed to a commonly known mildly corrosive media such as NaCl. The results obtained reveal an increase in hardness (assessed through either HRB) and (microhardness HV) in the quenched and annealed sample, as well as better corrosion resistance. The characterization was carried out through optical microscopy, Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), potentiodynamic polarization tests and electrochemical impedance spectroscopy.

The role played by science and technology parks (STPs) in technology transfer, industrial innovation, and economic growth is examined in this paper. The accurate monitoring of their evolution and impact is hindered by the lack of uniformity in STP models or goals, and the scarcity of high-quality datasets. This work uses existing terminologies, definitions, and core features of STPs to conduct a multidimensional data analysis that explores and evaluates the 21 core features which describe the key internal factors of an STP. The core features are gathered from a reliable and updatable dataset of Spanish STPs. The methodological framework can be replicated for other STP contexts and is based on descriptive techniques and machine-learning tools. The results of the study provide an overview of the general situation of STPs in Spain, validate the existence and characteristics of three types of STPs, and identify the typical features of STPs. Moreover, the prototype STP can be used as a benchmark so that other STPs can identify the features that need to be improved. Finally, this work makes it possible to carry out classifications of STPs, in addition to prediction and decision making for innovation ecosystems.

The corrosion inhibition efficiency, η, of sodium (6R,7R)-3-[(acetoxy)methyl]-8-oxo-7-[(2-thienylacetyl)amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, cephalothin, was evaluated in the system API 5L X52/1 M HCl, using electrochemical impedance spectroscopy and SEM analysis. The results showed that the inhibition mechanism involves blockage of the steel surface by the inhibitor molecules through a Langmuir-type adsorption process. The studies to determine the durability where the inhibitor remained effective showed that, at stagnant conditions, the η was maintained over 92% for up to 600 immersion hours at 50 ppm, reaching the best corrosion efficiency when temperature was 25 °C. Keywords: Electrochemical techniques, Corrosion inhibitor, Organic compounds, Adsorption

The design and synthesis of a series of theophylline derivatives containing 1,2,3-triazole moieties are presented. The corrosion inhibition activities of these new triazole–theophylline compounds were evaluated by studying the corrosion of API 5 L X52 steel in 1 M HCl medium. The results showed that an increase in the concentration of the theophylline–triazole derivatives also increases the charge transference resistance (Rct) value, enhancing inhibition efficiency and decreasing the corrosion process. The electrochemical impedance spectroscopy under static conditions studies revealed that the best inhibition efficiencies (approx. 90%) at 50 ppm are presented by the all-substituted compounds. According to the Langmuir isotherm, the compounds 4 and 5 analysed exhibit physisorption–chemisorption process, with exception of the hydrogen 3, bromo 6 and iodo 7 substituted compounds, which exhibit chemisorption process. The corrosion when submerging a steel bar in 1 M HCl was studied using SEM-EDS. This experiment showed that the corrosion process decreases considerably in the presence of 50 ppm of the organic inhibitors. Finally, the theoretical study showed a correlation between EHOMO, hardness (η), electrophilicity (W), atomic charge and the inhibition efficiency in which the iodo 7 substituted compound presents the best inhibitor behaviour.

The working area of a screen-printed electrode, SPE, was modified with the enzyme tyrosinase (Tyr) using different immobilization methods, namely entrapment with water-soluble polyvinyl alcohol (PVA), cross-linking using glutaraldehyde (GA), and cross-linking using GA and human serum albumin (HSA); the resulting electrodes were termed SPE/Tyr/PVA, SPE/Tyr/GA and SPE/Tyr/HSA/GA, respectively. These biosensors were characterized by means of amperometry and EIS techniques. From amperometric evaluations, the apparent Michaelis-Menten constant, Km′, of each biosensor was evaluated while the respective charge transfer resistance, Rct, was assessed from impedance measurements. It was found that the SPE/Tyr/GA had the smallest Km′ (57 ± 7) µM and Rct values. This electrode also displayed both the lowest detection and quantification limits for catechol quantification. Using the SPE/Tyr/GA, the Trolox Equivalent Antioxidant Capacity (TEAC) was determined from infusions prepared with “mirto” (Salvia microphylla), “hHierba dulce” (Lippia dulcis) and “salve real” (Lippia alba), medicinal plants commonly used in Mexico.

This work deals with the formation of supramolecular complexes between ascorbic acid (AA), the guest, and β-cyclodextrin (β-CD), the host, that was first potentiodynamically immobilized on the surface of a carbon paste electrode (CPE) throughout the formation of a β-CD-based conducting polymer (poly-β-CD). With the bare CPE and the β-CD-modified CPE, an electrochemical study was performed to understand the effect of such surface modification on the electrochemical response of the AA. From this study it was shown that on the modified-CPE, the AA was surface-immobilized through formation of an inclusion complex with β-CD, which provoked the adsorption of AA in such a way that this stage became the limiting step for the electrochemical oxidation of AA. Moreover, from the analysis of the experimental voltammetric plots recorded during AA oxidation on the CPE/poly-β-CD electrode surfaces, the Gibbs’ standard free energy of the inclusion complex formed by the oxidation product of AA and β-CD has been determined for the first time, ∆G0inclus = −36.4 kJ/mol.

Objetivos: Las ontologías son un recurso que permite trabajar informáticamente con la conceptualización del significado y evitar la limitación impuesta por los términos normalizados. El objetivo de este estudio es establecer el grado de usabilidad de las terminologías para el diseño de ontologías, que contribuyan a resolver los problemas de interoperabilidad semántica, y de reutilización de conocimiento en los sistemas de información clínicos. Métodos: Se han analizado 6 de las terminologías más relevantes para el ámbito clínico, epidemiológico, documental y administrativo-económico. Se valoraron las siguientes cualidades: cobertura conceptual, estructura jerárquica, granularidad conceptual, relaciones conceptuales y grado de formalismo utilizado en la representación conceptual, para establecer el grado de usabilidad. Resultados: Se consideran como ontologías ligeras los MeSH, los DeCS y el UMLS, aunque con diferencias entre ellas, al explicitar los conceptos, el tipo de relación y las restricciones entre los conceptos asociados. SNOMED y GALEN, con su formalismo declarativo basado en descripciones lógicas, incluyen la explicitación de las cualidades, una mayor restricción para relacionar conceptos y las reglas de combinación entre ellos, por lo que se consideran como ontologías pesadas. Conclusiones: El análisis de la representación declarada de las terminologías muestra las posibilidades de su reutilización como ontologías. Su grado de usabilidad dependerá de si se pretende que los sistemas de información clínicos resuelvan los problemas de interoperabilidad semántica (ontologías ligeras) o además reutilizar su conocimiento para sistemas de ayuda a la toma de decisiones (ontologías pesadas) y para tareas de recuperación, extracción y clasificación de información no estructurada.Objectives: Ontologies are a resource that allow the concept of meaning to be represented informatically, thus avoiding the limitations imposed by standardized terms. The objective of this study was to establish the extent to which terminologies could be used for the design of ontologies, which could be serve as an aid to resolve problems such as semantic interoperability and knowledge reusability in healthcare information systems. Methods: To determine the extent to which terminologies could be used as ontologies, six of the most important terminologies in clinical, epidemiologic, documentation and administrative-economic contexts were analyzed. The following characteristics were verified: conceptual coverage, hierarchical structure, conceptual granularity of the categories, conceptual relations, and the language used for conceptual representation. Results: MeSH, DeCS and UMLS ontologies were considered lightweight. The main differences among these ontologies concern conceptual specification, the types of relation and the restrictions among the associated concepts. SNOMED and GALEN ontologies have declaratory formalism, based on logical descriptions. These ontologies include explicit qualities and show greater restrictions among associated concepts and rule combinations and were consequently considered as heavyweight. Conclusions: Analysis of the declared representation of the terminologies shows the extent to which they could be reused as ontologies. Their degree of usability depends on whether the aim is for healthcare information systems to solve problems of semantic interoperability (lightweight ontologies) or to reuse the systems' knowledge as an aid to decision making (heavyweight ontologies) and for non-structured information retrieval, extraction, and classification.

Nuestro trabajo pretende presentar reunidos los textos epigráficos dispersos en varias publicaciones y que no han sido recogidos en el libro del doctor José Vives Inscripciones cristianas de España romana y visigoda, Barcelona 1942, última gran colección publicada de tales epígrafes. De la serie de vientimueve inscripciones que publicamos hoy, sólo seis han salido a luz después de 1942. Las demás habían aparecido ya antes de ese año. En algunos se ve el motivo de haber sido rechazadas por Vives, habiendo sido recogidas aq>uí cuando su fecha y carácter cristiano son discutibles y bastante probables.