A detailed Auger electron spectroscopy study of the first stages of the growth of C60 thin films

In this work we take advantage of the large sensitivity and in-depth resolution of Auger electron spectroscopy to study in a detailed way the growth of C60 over different substrates, namely Cu(111), Si(100) and graphene. The ability of AES, as compared to more local probes like STM or AFM, to follow the process in a dynamical way, allows us to study the growth of C60 below and over one ML, including the change of C60 over either Si or Cu to the growth of C60 over a C60 film. We found that the growth proceeds always as layer by layer. This result shows that differences in diffusion barriers are not as important as one can think following the idea of diffusion by a jumping mechanism. We propose that the sticking coefficient, governed by the adsorption energy, is the responsible of the differences observed between Cu and Si. Our results also point out to a different charge transfer among fullerene molecules and these surfaces. The same result is suggested in the case of C60 over graphene, but in this case our conclusion comes from the variable temperature experiments.Fil: Vidal, Ricardo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; ArgentinaFil: Ferron, Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; Argentin

Growth, thermal desorption and low dose ion bombardment damage of C60 films deposited on Cu(111)

Auger Electron Spectroscopy (AES), Low Energy Electron Diffraction (LEED) and Reflection Electron Energy Loss Spectrometry (REELS) were used to characterize the growth and thermal stability of C60 films deposited on Cu(111). By means of LEED we found that while C60 grows in an ordered fashion up to the first monolayer (ML) at room temperature (RT), it turns amorphous beyond that point. On the other hand, when the substrate temperature is kept at 450K films up to two ML with crystalline structure are obtained. For substrate temperatures beyond 570K thick films (more than 1 ML) do not grow at all. By using AES, we found that a thick C60 film starts to desorb at a temperature around 470K but the first monolayer remains stable up to temperatures as high as 900K. A monolayer with a better crystalline order is obtained after desorption than that growth with the substrate at RT or higher temperatures. When the substrate is heated at 970K, the first monolayer is not fully removed but the C60 molecular structure is altered or molecules break up into smaller pieces. The ion induced damage on C60 on Cu(111) films was studied for typical ions, incoming energies and irradiation doses used in Low Energy Ion Scattering (LEIS) experiments. The D-value of C(KLL) Auger spectra and the -plasmon of REELS, were monitored to characterize the damage caused to the film. We found that, at low doses ( 1014 ions/cm2), damage is only detectable for massive ions like Ar, but not for H and He in the 2-8 keV range.Fil: Bonetto, Fernando Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Departamento de Materiales; ArgentinaFil: Vidal, Ricardo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Departamento de Física; ArgentinaFil: Quintero Riascos, Vanessa Alexandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; ArgentinaFil: Bonin, Claudio Julio. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; ArgentinaFil: Ferron, Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Departamento de Materiales; Argentin

Estimationof the energy saving potentials in foundry industries based on iso 50001

This paper presents the application of tools to develop a procedure to estimate the energy saving potentials in a small foundry company in Colombia, based on the ISO 50001 standard. This work was carried within the framework of a national industrial project, funded by UNIDO, aimed at the small and medium industrial sector companies (SMEs) of Valle del Cauca, to establish the requirements that are needed to implement an energy management system. With the aim of increasing the energy efficiency of the processes, the energy planning process proposed by ISO 50001 is carried out, whose lead to the establishment of concrete and attainable goals, as well as to the proposal of various improvement plans regarding savings and efficient use of energy. As a result, the savings potentials for the different production levels were estimated, which represents a saving of 15984.25 kWh, which corresponds to 8.7% of the total energy consumed in the 10 months analyzed, and a value of 1486 US

Changes in Alcohol Use during the COVID-19 Pandemic among Young Adults: The Prospective Effect of Anxiety and Depression

Versión editorHealth measures instantiated to reduce the spread of COVID-19 have imposed significant constraints for the population and impacted on drinking habits and mental health. This study longitudinally compared changes in alcohol consumption before and after the COVID-19 outbreak and the impact of sociodemographic and mental health variables on such changes among a community sample of young adults. Data were collected in the context of a larger, ongoing longitudinal study. The sample consisted of 305 young adults from Spain aged between 18 and 26 years (mean age = 21.27, (SD = 2.21), female = 53.4%; college students = 61.6%) who completed first (November-2019 and February-2020; i.e., before the outbreak of COVID-19) and second follow-up questionnaires (March 2021, a year after the COVID-19 outbreak). Alcohol use (quantity and drinking frequency), depression and anxiety symptoms were measured. Quantity and frequency of alcohol use decreased from the preto post-COVID-19 period. A decrease in drinking frequency was observed among college students, but not in noncollege peers. Although we found no effect of pre-COVID-19 anxiety on alcohol use changes, those with more depressive symptoms at the pre-COVID assessment were more resistant to decreasing their drinking quantity and frequency after the COVID-19 outbreak. This information will be of value when designing interventions aimed at reducing harmful alcohol use and highlights the role of mental health status when identifying high risk populations of young-adults during this, and future, public health crisesFunding for this study was provided by the Consejería de Salud (Junta de Andalucía, Andalucía, Spain) under Grant Number PI-0503-2018 (Principal Investigator: Fermín Fernández Calderón). BV was supported by Fundación Carolina and SEGIB, and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET

Morphology and thermal stability of alf3 on Cu(100) thin films

Se estudió el crecimiento de películas epitaxiales ultra-delgadas de fluoruro de aluminio en Cu (100) mediante una combinación de técnicas experimentales de física de superficies. La deposición a temperatura ambiente resulta en la decoración de escalones seguida por la formación de islas dendríticas bidimensionales que coalescen para formar películas porosas. Las películas ultra-delgadas (de hasta dos monocapas de espesor) resultan morfológicamente inestables al calentar; parte de la película deja de mojar la superficie del sustrato a alrededor de 430 K con la formación de islas tridimensionales y dejando expuesta un área extensa de la superficie de Cu. En cambio, películas de varios nanómetros de espesor son estables hasta temperaturas cercanas a los 730 K cuando ocurre la desorción molecular. El efecto de la irradiación electrónica también ha sido caracterizado mediante diferentes técnicas espectroscópicas; encontrando que incluso dosis de irradiación reducidas de electrones pueden producir una descomposición significativa del fluoruro de aluminio, resultando en la liberación de moléculas de flúor y la formación de aluminio metálico. Estas características hacen del fluoruro de aluminio un material interesante para aplicaciones en espintrónica.Fil: Ruano Sandoval, Gonzalo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); ArgentinaFil: Moreno López, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); ArgentinaFil: Passeggi, Mario Cesar Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); ArgentinaFil: Vidal, Ricardo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); ArgentinaFil: Ferron, Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); ArgentinaFil: Niño, M. A.. Universidad Autónoma de Madrid; EspañaFil: Miranda, R.. Universidad Autónoma de Madrid; EspañaFil: de Miguel, J. J.. Universidad Autónoma de Madrid; Españ

Kinetics of digestion of low-quality forage grazed by beef cattle fed supplements containing increasing levels of rumen undegradable protein

This experiment was conducted to evaluate the degradation kinetics and microbial efficiency of beef cattle grazing on low-quality forage and receiving supplements with different levels of rumen undegradable protein (RUP). The animals grazed on palisade grass pasture solely or this pasture and supplement containing 40 or 60 g of RUP per 100 g of crude protein (CP). The degradation profiles of neutral detergent fiber, fiber carbohydrates, and neutral detergent insoluble protein were interpreted kinetically by using a decreasing logistic model. Treatments (no supplement, or RUP at 40 or 60 g−1 100 g CP) did not affect rumen fill; however, the increase in the indigestible fiber carbohydrate fraction that occurred at the expense of the digestible fiber carbohydrate fraction resulted in a greater rumen fill effect. The palisade grass showed a significant proportion of its nitrogen in the form of slowly degradable protein as neutral detergent insoluble protein, which amounted to 26 g per 100 g CP. Supplementation with 40 g of RUP per 100 g CP decresead the indigestible fraction of the low-quality forage. However, the absence of a rumen-fill effect demonstrates that the additional supply of nutrients contributes greatly to increasing growth efficiency and use of the available energy from the forage by the ruminal microorganisms

Atributos físicos y fisiológicos de las semillas de café (Coffea arabica L)

Coffee is one of the most consumed and traded beverages worldwide and also the source of livelihood for millions of people. Knowledge of physical characteristics is essential for the design and manufacture of equipment for processing of coffee beans. This work was carried out in the seed laboratory of the Universidad National Agraria La Molina using 12 accessions of Coffea arabica. In each genetic material, physical and physiological characteristics were quantified such as polar and equatorial diameter, and thickness, as well as arithmetic diameter, geometric diameter, degree of sphericity, surface area, volume and percentage of germination/volume and germination percentage. The results indicated that UNACAF-172 and UNACAF-146 showed greater polar, arithmetic and geometric diameter. In addition, they showed greater surface area, volume and seedling weight. On the contrary, these same accessions had a lower germination percentage. Similarly, UNACAF-119 and UNACAF-90 showed low physical attributes, although high germination percentage and low seedling weight. In conclusion, the genetic component plays an important role in the physical and physiological attributes of coffee seeds.El café es una de las bebidas más consumidas y comercializadas a nivel mundial, y además la fuente de sustento para millones de personas. El conocimiento de las características físicas es esencial para el diseño y fabricación de equipos para el beneficio del grano. Este trabajo se realizó en el laboratorio de semillas de la Universidad Nacional Agraria La Molina usando 12 accesiones de Coffea arabica. En cada material genético se cuantificaron las características físicas y fisiológicas, como el diámetro polar, ecuatorial y el grosor, así también el diámetro aritmético, diámetro geométrico, grado de esfericidad, área superficial, volumen y porcentaje de germinación. Los resultados indicaron que UNACAF-172 y UNACAF-146 mostraron mayor diámetro polar, aritmético y geométrico. Además, presentaron mayor área superficial, volumen y peso de plántula. Al contrario, estas mismas accesiones tuvieron menor porcentaje de germinación. Asimismo, UNACAF-119 y UNACAF-90 mostraron bajos atributos físicos, aunque alto porcentaje de germinación y bajo peso de plántulas. En conclusión, el componente genético tiene un papel importante en los atributos físicos y fisiológicos de las semillas de café

Porcine Protein Hydrolysates (PEPTEIVA®) Promote Growth and Enhance Systemic Immunity in Gilthead Sea Bream (Sparus aurata)

The effects of porcine plasma protein hydrolysate (PPH) on growth, feed efficiency, and immune responses was evaluated in Sparus aurata. Fish were fed two isoproteic (48% protein), isolipidic (17% fat), and isoenergetic diets (21.7 MJ/kg) diets, one of them containing 5% PPH at the expense of fishmeal. Both diets were tested for 92 days. A significant increase in growth was observed in fish fed the PPH diet in comparison to the control group (182.2 ± 4.4 vs. 173.8 ± 4.1 g), as well as an increase in feed intake without worsening FCR values. An ex vivo assay, with splenocytes incubated with lipopolysaccharide, was conducted to evaluate the cellular immune competence of fish. Genes involved in humoral immunity (lys, IgM), pro- (tnf-α, il-1β), and anti-inflammatory (tgf-β1, il10) cytokines were upregulated in the PPH group in comparison to the control group. The inclusion of PPH in diets enhanced the antibacterial capacity of skin mucus, as the co-culture of selected bacteria (E. coli, V. anguillarum, and P. anguilliseptica) with skin mucus indicated. The present results showed that the PPH in low fishmeal diets (2%) promoted growth and feed efficiency, as well as enhancing the immune response, which indicates that this is a safe and functional ingredient for aquafeeds.info:eu-repo/semantics/publishedVersio

Implementación e desenvolvemento de aulas de xeometría euclídea e diferencial en Sage

Este libro é continuación do manual "Implementación e desenvolvemento de aulas de matemáticas avanzadas en SAGE" (IDAMAS) publicado pola Universidade de Vigo en 2018 e dedícase ao tratamento en Sage da xeometría euclídea e xeometría diferencial, que son parte esencial na formación do enxeñeiro e, en particular, do enxeñeiro industrial. IDAMAS debe ser considerado unha lectura necesaria para extraer toda a utilidade a este segundo libr

Porcine Protein Hydrolysates (PEPTEIVA ) Promote Growth and Enhance Systemic Immunity in Gilthead Sea Bream (Sparus aurata)

The effects of porcine plasma protein hydrolysate (PPH) on growth, feed efficiency, and immune responses was evaluated in Sparus aurata. Fish were fed two isoproteic (48% protein), isolipidic (17% fat), and isoenergetic diets (21.7 MJ/kg) diets, one of them containing 5% PPH at the expense of fishmeal. Both diets were tested for 92 days. A significant increase in growth was observed in fish fed the PPH diet in comparison to the control group (182.2 ± 4.4 vs. 173.8 ± 4.1 g), as well as an increase in feed intake without worsening FCR values. An ex vivo assay, with splenocytes incubated with lipopolysaccharide, was conducted to evaluate the cellular immune competence of fish. Genes involved in humoral immunity (lys, IgM), pro- (tnf-α, il-1β), and anti-inflammatory (tgf-β1, il10) cytokines were upregulated in the PPH group in comparison to the control group. The inclusion of PPH in diets enhanced the antibacterial capacity of skin mucus, as the co-culture of selected bacteria (E. coli, V. anguillarum, and P. anguilliseptica) with skin mucus indicated. The present results showed that the PPH in low fishmeal diets (2%) promoted growth and feed efficiency, as well as enhancing the immune response, which indicates that this is a safe and functional ingredient for aquafeeds