Modeling of primary dendrite arm spacing variations in thin-slab casting of low carbon and low alloy steels

Solidification structure of a High Strength Low Alloy (HSLA) steel, in terms of dendrite arm spacing distribution across the shell thickness, is studied in a breakout shell from a thin-slab caster at Tata Steel in IJmuiden. Columnar dendrites were found to be the predominant morphology throughout the shell with size variations across the shell thickness. Primary Dendrite Arm Spacing (PDAS) increases by increasing the distance from meniscus or slab surface. Subsequently, a model is proposed to describe the variation of the PDAS with the shell thickness (the distance from slab surface) under solidifiction conditions experienced in the primary cooling zone of thin-slab casting. The proposed relationship related the PDAS to the shell thickness and, hence, can be used as a tool for predicting solidifcation structure and optimizing the thin-slab casting of low alloy steels

Estimating numerical errors due to operator splitting in global atmospheric chemistry models: Transport and chemistry

We present upper bounds for the numerical errors introduced when using operator splitting methods to integrate transport and non-linear chemistry processes in global chemical transport models (CTM). We show that (a) operator splitting strategies that evaluate the stiff non-linear chemistry operator at the end of the time step are more accurate, and (b) the results of numerical simulations that use different operator splitting strategies differ by at most 10 percent, in a prototype one-dimensional non-linear chemistry-transport model. We find similar upper bounds in operator splitting numerical errors in global CTM simulations

Effect of V and N on the microstructure evolution during continuous casting of steel

Low Carbon (LC) steel is not expected to be sensitive to hot tearing and/or cracking while microalloyed steels are known for their high cracking sensitivity during continuous casting. Experience of the Direct Sheet Plant caster at Tata Steel in Ijmuiden (the Netherlands), seems to contradict this statement. It is observed that a LC steel grade has a high risk of cracking alias hot tearing, while a High Strength Low Alloyed (HSLA) steel has a very low cracking occurrence. Another HSLA steel grade, with a similar composition but less N and V is however very sensitive to hot tearing. An extreme crack results in a breakout. A previous statistical analysis of the breakout occurrence reveals a one and a half times higher possibility of a breakout for the HSLA grade compared to the LC grade. HSLA with extra N, V shows a four times smaller possibility of breakout than LC. This study assigns the unexpected effect of the chemical composition on the hot tearing sensitivity to the role of some alloying elements such as V and N as structure refiners.This research was carried out under project number M41.5.08320 within the framework of the Research Program of the Materials innovation institute M2i (www.m2i.nl)

La Nueva España en dos novelas históricas del siglo XIX : el inquisidor de México y Trinidad de Juárez

1 archivo PDF (16 páginas). fhquadragintatresSe realiza el análisis de dos obras: El inquisidor de México (1838), de José Joaquín Pesado (1801-1861) y Trinidad de Juárez (1868), de Manuel Payno (1832-1896), donde se desarrolla la concepción de la "novela decimonónica mexicana como novela del incesto, desde luego como asunto preponderante, se complementa con las nociones de orfandad, identidad/alteridad, y desarticulación/desaparición del núcleo familiar. Palabras clave: Novela histórica. Siglo XIX. Nueva España. El inquisidor de México, Trinidad de Juárez. Manuel Payno. José Joaquín Pesado

Border Culture, Mexican Identity, Class, And Media Consumption: A Look Into “Fresa” High School Students

The border strip between the south of the United States and the north of Mexico provide an excellent opportunity to study the effects of the flow of media productions from the United States to Mexico. Many communication theories have attempted to explain the reception of transnational media flows to Latin American countries. Scholars from the cultural imperialism camp argue that the flow of culture is unidirectional from capitalist or First World countries (mainly the United States) to developing countries (also know as the Global South); other theories claim there is an asymmetrical dependence between developed and underdeveloped countries (Fejes, 1981). However, recent arguments claim audiences tend to prefer content closely related to their own cultural values (Straubhaar, 1991). Audience research has concluded there is no evidence to support the loss of cultural identity in some Latin American countries and regions according to their media preference (Straubhaar, 1991 Lozano, 1992). Nonetheless, those studies have also found that regardless of the geographical or cultural proximity to the United States or Europe, upper and middle class audiences tend to prefer to a certain degree US media content or international programming over domestic programming. Combining those two theoretical propositions, the purpose of this study is to look at the media consumption preferences of high school students in Nuevo Laredo, Tamaulipas and find a relation between the cultural products they consume, their sense of Mexican identity, and nationalism. Using both methodological approaches, quantitative and qualitative, a survey was conducted with students from three different private high schools in Nuevo Laredo and a total of 22 participants were interviewed in separate focus groups. One of the most important findings of this study is that upper-middle and upper class students from Nuevo Laredo are not worried about losing their Mexican identity as a consequence of continuous exposure to American media. It could be argued that they are more afraid of not being able to attain the best from what their privileged geographical location has to offer in terms of cultural capital. They recognize that one of the biggest advantages of living in the border with the United States is the ability to practice while learning English and to have access to American products

Sobre "El Iris" de Linati y "Los mexicanos pintados por sí mismos"

1 archivo PDF (13 páginas). fhquadragintaunusEn este artículo se destaca los nexos entre la génesis de la litografía nacional y el proceso de construcción del perfil de México y lo mexicano. Por medio del análisis de los ideales carbonarios y de la convicción masónica de José María Heredia, Claudio Linati y Florencio Galli, editores del periódico El Iris, se destaca la defensa que este diario hizo de los ideales de libertad, república y democracia. Dicha revista estableció, además, el panteón de los héroes de la independencia, del que eliminó a Agustín de Iturbide. Se revisa finalmente en este artículo, Los Mexicanos pintados por sí mismos, obra escrita “por una sociedad de literatos de México” la cual, tiene el mérito de ser el primer libro de este tipo elaborado por mexicanos, en un acercamiento a la vida cotidiana, en el que intervinieron tanto los litógrafos como las plumas más destacadas del momento

Las intervenciones en la adolescencia para la prevención del VIH/Sida

Trabajo fin de grado en EnfermeríaEl VIH/Sida, es una infección de gran magnitud, que destruye el sistema inmunitario del organismo, permitiendo la adquisición de enfermedades oportunistas y/o cáncer. Los adolescentes son una población vulnerable a la adquisición del VIH, ya que se encuentran en una etapa de transición, en la que sufren diferentes cambios y dónde determinados factores propios y externos les posibilitan la adquisición de la infección. Es por ello que el uso de la prevención, cobra especial relevancia como medida para proteger la salud reproductiva, en especial la aplicación de intervenciones preventivas que permitan la elaboración de estrategias ante situaciones de riesgo sexual. La incorporación de este tipo de intervenciones va a potenciar el desarrollo de habilidades (toma de decisiones, autoeficacia, comunicación, uso consistente del condón) y el aumento de conocimientos acerca del VIH/Sida. Objetivo: Determinar las intervenciones preventivas que modifican o aumentan los conocimientos acerca del VIH/Sida. Metodología: Revisión narrativa realizada a partir de las búsqueda bibliográficas en las bases de datos de Pubmed, Cuiden, Cinahl y Scielo. Conclusiones: Las intervenciones preventivas no sólo se centran en el aumento de los conocimientos, también tienen en cuenta la adquisición de habilidades para prevenir la infección, ya que el aumento de conocimientos no es suficiente para la modificación de los comportamientos de riesgo. La incorporación de enfermería, padres, TICs e intervenciones adaptadas a la población, posibilitan la eficacia de las intervenciones preventivas.HIV / AIDS is an infection of great magnitude, which destroys the body's immune system, allowing the acquisition of opportunistic diseases and/or cancer. Adolescents are a vulnerable population to the acquisition of HIV, since they are in a transition stage, in which they suffer different changes and where certain own and external factors allow them to acquire the infection. For this reason, the use of prevention is especially important as a measure to protect reproductive health, especially the application of preventive interventions that allow the development of strategies in situations of sexual risk. Their incorporation into these interventions will enhance the development of skills (decision-making, self-efficacy, communication, consistent condom use) and increased knowledge about HIV / Aids. Objective: To determine preventive interventions that modify or increase knowledge about HIV/Aids. Methodology: Narrative review based on a bibliographic searches in Pubmed, Cuiden, Cinahl and Scielo databases. Conclusions: Preventive interventions aimed at increasing knowledge also take into account the acquisition of skills to prevent infection, since the increase of knowledge is not sufficient for the modification of risk behaviors. The incorporation of nursing, parents, ICTs and interventions adapted to the population, make possible the efficiency of the preventive interventions

Dataset concerning the analytical approximation of the Ae3 temperature.

In this paper we present a new polynomial function for calculating the local phase transformation temperature (Ae3 ) between the austenite+ferrite and the fully austenitic phase fields during heating and cooling of steel:[Formula: see text] The dataset includes the terms of the function and the values for the polynomial coefficients for major alloying elements in steel. A short description of the approximation method used to derive and validate the coefficients has also been included. For discussion and application of this model, please refer to the full length article entitled "The role of aluminium in chemical and phase segregation in a TRIP-assisted dual phase steel" 10.1016/j.actamat.2016.05.046 (Ennis et al., 2016) [1]

The Threat of Climate Change on Alpine Birds and Their Habitats.

Alpine birds are high-elevation specialists with unique adaptations such as delayed and reduced breeding and the physiological ability to withstand hypoxic, arid, and windy conditions—unfortunately, their populations are expected to decline due to anthropogenic climate change. These birds are short-migrating species, usually only migrating vertically up to the highest peaks for the breeding season. With the changing landscape and climate, scientists have been trying to understand the risk alpine birds face and whether they will change their distribution or decline. Abiotic changes such as drastic retreating of glaciers, reduced snowpack, increased temperatures, and increased precipitation as rain are shrinking the available breeding and foraging habitat of alpine birds. Indirectly, these abiotic changes are triggering biotic changes; for example, forest and shrub vegetation are invading alpine tundra, and snowpack decline is reducing snowbed habitat available for foraging. Additionally, the environmental cues triggered at lower elevations are becoming increasingly mismatched with higher elevation conditions, causing birds to migrate earlier to regions that are still completely covered in snow. Studies focused on understanding alpine bird responses to climate change have found heterogeneity in the birds’ responses. Unfortunately, this complicates conservation efforts because it limits our ability to apply one species’ response to another. Going forward, conservation efforts should focus on understanding specific bird ecology and on restoring and protecting alpine habitats