Analysis of Ostwald ripening in Ni-rich Ni–Ti alloys by diffusion couples

"The coarsening kinetics of gamma' precipitates in Ni-rich Ni-Ti alloys are studied using a Ni-11-5 wt% Ti and pure Ni diffusion couple. The formed concentration gradient allowed to study the aging process at 1023 K (750 degrees C) in Ni-rich Ni Ti alloys with Ti content from 8-62 to 11-15 wt% Ti. In general, during the coarsening of gamma' precipitates, the experimental coarsening kinetics do not fit well to the LSW or TIDC theoretical models and anomalous behaviour of coarsening rate constant (k(r)) associated with gamma' volume-fraction is confirmed at high values.

Coupling Mars Ground and Orbital Views: Generate Viewsheds of Mastcam Images From the Curiosity Rover, Using ArcGIS® and Public Datasets

The Mastcam (Mast Camera) instrument onboard the NASA Curiosity rover provides an exclusive view of Mars: High‐resolution color images from Mastcam allow users to study Gale crater's geologic terrains along Curiosity's path. These ground observations complement the spatially broader views of Gale crater provided by spacecrafts from orbit. However, for a given Mastcam image, it can be challenging to locate the corresponding terrains on the orbital view. No method for locating Mastcam images onto orbital images had been made publicly available. The procedure presented here allows users to generate Mastcam image viewsheds, using ArcGIS® software, its built‐in Viewshed tool®, and public Mars datasets. This procedure locates onto Mars orbital view the terrains that are observed in a given Mastcam image. Because this procedure uses public datasets, it is applicable to available Mastcam images and to the future ones that will be acquired along the Curiosity rover's path. This procedure can be used by the public to assess scientific questions regarding Martian surface processes and geologic history. In addition, this procedure can be utilized as pedagogic GIS material by the Geosciences or Planetary Sciences communities, for enhancing students' skillsets in GIS and provide students with experience working with datasets from both orbiter and rover Mars missions

Coupling Mars Ground and Orbital Views: Generate Viewsheds of Mastcam Images From the Curiosity Rover, Using ArcGIS® and Public Datasets

The Mastcam (Mast Camera) instrument onboard the NASA Curiosity rover provides an exclusive view of Mars: High‐resolution color images from Mastcam allow users to study Gale crater's geologic terrains along Curiosity's path. These ground observations complement the spatially broader views of Gale crater provided by spacecrafts from orbit. However, for a given Mastcam image, it can be challenging to locate the corresponding terrains on the orbital view. No method for locating Mastcam images onto orbital images had been made publicly available. The procedure presented here allows users to generate Mastcam image viewsheds, using ArcGIS® software, its built‐in Viewshed tool®, and public Mars datasets. This procedure locates onto Mars orbital view the terrains that are observed in a given Mastcam image. Because this procedure uses public datasets, it is applicable to available Mastcam images and to the future ones that will be acquired along the Curiosity rover's path. This procedure can be used by the public to assess scientific questions regarding Martian surface processes and geologic history. In addition, this procedure can be utilized as pedagogic GIS material by the Geosciences or Planetary Sciences communities, for enhancing students' skillsets in GIS and provide students with experience working with datasets from both orbiter and rover Mars missions

Structural, mechanical and electronic properties of two-dimensional structure of III-arsenide (1 1 1) binary compounds: An ab-initio study

Structural, mechanical and electronic properties of two-dimensional single-layer hexagonal structures in the (1 1 1) crystal plane of IIIAs-ZnS systems (III = B, Ga and In) are studied by first-principles calculations based on density functional theory (DFT). Elastic and phonon dispersion relation display that 2D h-IIIAs systems (III = B, Ga and In) are both mechanical and dynamically stable. Electronic structures analysis show that the semiconducting nature of the 3D-IIIAs compounds is retained by their 2D single layer counterpart. Furthermore, density of states reveals the influence of σ and π bonding in the most stable geometry (planar or buckled) for 2D h-IIIAs systems. Calculations of elastic constants show that the Young's modulus, bulk modulus and shear modulus decrease for 2D h-IIIAs binary compounds as we move down on the group of elements of the periodic table. In addition, as the bond length between the neighboring cation-anion atoms increases, the 2D h-IIIAs binary compounds display less stiffness and more plasticity. Our findings can be used to understand the contribution of the σ and π bonding in the most stable geometry (planar o buckled) for 2D h-IIIAs systems. Structural and electronic properties of h-IIIAs systems as a function of the number of layers have been also studied. It is shown that h-BAs keeps its planar geometry while both h-GAs and h-InAs retained their buckled ones obtained by their single layers. Bilayer h-IIIAs present the same bandgap nature of their counterpart in 3D. As the number of layers increase from 2 to 4, the bandgap width for layered h-IIIAs decreases until they become semimetal or metal. Interestingly, these results are different to those found for layered h-GaN. The results presented in this study for single and few-layer h-IIIAs structures could give some physical insights for further theoretical and experimental studies of 2D h-IIIV-like systems

Analysis of the Relationship between Lifestyle and Coffee Consumption Habits, from the Myth Approach, in the Municipalities of Orizaba, Tehuipango, and Zongolica Veracruz.

Coffee consumption habits have evolved along with society for more than 300 years around the world. Social changes imply different lifestyles in each culture. Lifestyles influence the myths used by people in their consumption decisions. The objective of this research is to determine the relationship between lifestyle and coffee consumption habits, from the perspective of myth, in the inhabitants of the Mexican municipalities of Orizaba, Tehuipango, and Zongolica. A survey was conducted with a sample of inhabitants of the three municipalities studied. The statistical analyzes applied were the central limit theorem, Pearson, and Chi-square. The results show that the variables Consumption habits-Lifestyle-Myth, are highly dependent on the level of perception of people. It is concluded that the coffee myth corresponds to the "family union" in the study municipalities. This myth is not characterized in the evolutionary stages contemplated in the "waves of coffee"

Impacto del cambio climático en la adaptación del cultivo de café (Coffea arabica L.) en Tabasco, México

Objective: To define the actual best potential areas for growing coffee in Tabasco state and its expected potential yields. Also, define its new distribution in the year 2050 under a climatic change scenario, as well as the impact of this scenario on the future potential yields. Design/methodology/approach: The FAO AgroEcological Zoning (AEZ) methodology was used to define the best areas to grow coffee and to estimate their potential yield in Tabasco state under current era and on a future climate change scenario for the year 2050 (FAO, 1981). The AEZ performed for the 2050 year takes in account a 1.6°C increment in the mean daily temperature for the selected climatic stations in the present study. Results: The resulting overlapping map of soil and climate most suitable potential areas shows that in Tabasco coffee has been grown in not optimal agro ecological conditions. Actually the more suitable and optimal areas for arabic type coffee in Tabasco covers a 59,400.24 ha out of the existing total 2,034,227.52 ha. Limitations of study/implications: There is a large group of new coffee clones in Mexico which leaf area and harvest index are unknown, getting hard to estimate their potential yields. Findings/conclusions: In the year 2050, under the worst climatic change scenario, the actual best potential areas to grow coffee in Tabasco will be reduced in 96.42% and their potential yields will also be reduced in 67% compared to the actual potential yields.Objetivo: Determinar las áreas más aptas para cultivar café en el estado de Tabasco, así como su rendimiento potencial actual. Determinar su redistribución para el año 2050 bajo un escenario de cambio climático, así como determinar el impacto de este cambio sobre los rendimientos potenciales futuros. Diseño/Metodología/Aproximación: Para la Zonificación Agro-Ecológica (ZAE) y la estimación de los rendimientos potenciales del café en el estado de Tabasco en la época actual y para el año 2050 se siguió el procedimiento propuesto por la FAO (FAO, 1981). La ZAE para el año 2050 se realizó incrementando en 1.6 °C las temperaturas promedio diarias de las estaciones climatológicas selectas. Resultados: El álgebra de mapa de las zonas con alto potencial climático y las zonas con alto potencial edafológico, indica que, en el estado de Tabasco se ha estado cultivando café en zonas que no son las más óptimas para este tipo de café.  Las áreas óptimas para café tipo arábiga se reducen a solo 59,400.24 ha de las 2,034,227.52 ha que bajo las condiciones climáticas actuales existen. Limitaciones del estudio/implicaciones: Hay una amplia variedad de clones de café en México, de los cuales se desconoce el índice de área foliar e índice de cosecha, lo que dificulta estimar los rendimientos potenciales actuales. Hallazgos/conclusiones: Bajo el peor escenario de cambio climático, se reducirá en 92.46% las actuales áreas edafoclimáticamente muy aptas. El rendimiento potencial estimado actual para el café tipo arábiga, bajo el escenario de cambio climático para el año 2050, se verá reducido en promedio en 67%

Efecto del ácido giberélico y la 6-bencilaminopurina sobre el desarrollo de yemas en injertos de cacao (theobroma cacao l.)

Gran parte de los cultivos de cacao en el país son viejos y necesitan ser renovados debido a sus bajos rendimientos. Por esta razón se aborda la producción masiva de plántulas injertadas con materiales de alta productividad, que sin embargo presentan problemas en el prendimiento y desarrollo de las yemas. En el Centro de Investigación Nataima-Corpoica (Espinal, Tolima), plántulas de cacao del clon IMC67 tratadas con desbrote apical fueron injertadas con yemas de los clones CCN51 e ICS95. El ensayo siguió un diseño completamente aleatorizado con siete tratamientos, tres de ellos correspondientes a concentraciones de 5, 10 y 15 mg L-1 de ácido giberélico (AG3), y otros tres aplicando 6-bencilaminopurina (6BAP) en las mismas concentraciones, más un testigo sin aplicación de hormonas. Cada 3 días se midieron la altura, el diámetro, la longitud, el número de hojas y el área foliar del injerto, además de su masa fresca y seca al final del experimento, el cual duró 30 días. El AG3 permitió alcanzar los mayores valores en longitud, número de hojas, área foliar y masa fresca y seca del injerto. Para los mismos parámetros, los tratamientos con 6BAP alcanzaron valores similares a los obtenidos con AG3 (con diferencias estadísticas en algunos casos), además de los mayores diámetros del injerto. Dentro de las aplicaciones de AG3, la realizada a una concentración de 10 mg L-1 mostró los mejores resultados en ambos clones. Sin la aplicación de hormonas, las yemas del clon ICS95 desarrollaron una mayor área foliar y alcanzaron mayores valores de masa fresca y seca que las yemas del clon CCN51. Sin embargo, después de aplicar los tratamientos, los dos clones presentaron valores similares

Hydrogen Variability in the Murray Formation, Gale Crater, Mars

The Mars Science Laboratory (MSL) Curiosity rover is exploring the Murray formation, a sequence of heterolithic mudstones and sandstones recording fluvial deltaic and lake deposits that comprise over 350 m of sedimentary strata within Gale crater. We examine >4,500 Murray formation bedrock points, employing recent laboratory calibrations for ChemCam laser‐induced breakdown spectroscopy H measurements at millimeter scale. Bedrock in the Murray formation has an interquartile range of 2.3–3.1 wt.% H₂O, similar to measurements using the Dynamic Albedo of Neutrons and Sample Analysis at Mars instruments. However, specific stratigraphic intervals include high H targets (6–18 wt.% H₂O) correlated with Si, Mg, Ca, Mn, or Fe, indicating units with opal, hydrated Mg sulfates, hydrated Ca sulfates, Mn‐enriched units, and akageneite or other iron oxyhydroxides, respectively. One stratigraphic interval with higher hydrogen is the Sutton Island unit and Blunts Point unit contact, where higher hydrogen is associated with Fe‐rich, Ca‐rich, and Mg‐rich points. A second interval with higher hydrogen occurs in the Vera Rubin ridge portion of the Murray formation, where higher hydrogen is associated with Fe‐rich, Ca‐rich, and Si‐rich points. We also observe trends in the H signal with grain size, separate from chemical variation, whereby coarser‐grained rocks have higher hydrogen. Variability in the hydrogen content of rocks points to a history of water‐rock interaction at Gale crater that included changes in lake water chemistry during Murray formation deposition and multiple subsequent groundwater episodes