Reactive transport model for bentonites in COMSOL multiphysics: Benchmark and validation exercise.

At present, the deep geological repository concept for spent nuclear fuel is considered the most reliable and safe technique for the permanent disposal of this type of waste. One of the many safety elements used is an engineered barrier made of compacted bentonite. This material allows the encapsulated waste to be isolated from the host rock. Therefore, there is great interest in a detailed study of the behavior of bentonites to different changes in the composition of the surrounding groundwater. In this context, this work presents a new reactive transport model for bentonites implemented in the COMSOL Multiphysics platform. The model contemplates a non-simplistic geochemical system composed of 42 species and 4 minerals. Reactive transport involves the diffusive-dispersive-advective processes defined by the Nernst Planck equations for two overlapping modeling levels (macro- and microstructural) to simulate the behavior of double-porosity media. The uniqueness of this model is that the system of equations used to calculate the chemical speciation problem and the advective-diffusive-dispersive transport can be integrally solved in COMSOL. The model has been satisfactorily verified and validated using the benchmark exercise consisting of the simulation of the multicomponent advective-diffusive column experiment conducted on a compacted bentonite core extracted from a field experiment (LOT project) in the Äspö Hardrock laboratory (Sweden).

A worksheet-based tool to implement reactive transport models in COMSOL Multiphysics.

The increasing needs for modelling of reactive transport phenomena in different areas of environmental modelling have led to the development of many numerical codes. However, many of them suffer from a lack of flexibility, which hinders the adaptation of the codes to new problems. Moreover, in many cases, changes can be done by a very reduced group of people, and often by a single person, the main developer. Implementation platforms based on multiphysics modelling removes these barriers, although until now within that programming environments has been only possible the coupling of geochemical codes to transport equations using operator splitting techniques. This paper presents the EE4MGM tool, a MS Excel worksheet, provided in supplementary material, for the edition and complete implementation of reactive transport models in COMSOL. The tool automatically generates the code needed to solve the desired reactive transport problem by selecting only which species make up the geochemical system. This way, the numerical model will be completely adapted to the idealisation to be applied, being able to choose easily and effortlessly from a wide range of different levels of conceptual complexity. The organization of data input and the equation libraries obtained for the implementation in the multiphysics COMSOL environment are first described. Afterwards, two examples, in one and two-dimensional domains, to check the utility of the tool are presented.

Splanchnic vein thrombosis as a first manifestation of Primary myelofibrosis / Trombosis venosa esplácnica como manifestación inicial de mielofibrosis primaria

Myeloproliferative neoplasms are chronic disorders of clonal hematopoietic stem cells, characterized by an overproduction of functional granulocytes, red blood cells and / or platelets, and one of the major complications is the occurrence of venous and arterial thrombotic problems caused by increased platelet aggregation and thrombin generation. In this study 11 cases of primary myelofibrosis (PM) were evaluated and 2 debuted with splanchnic venous thrombosis (SVT); so after seeing the results of this study and of world literature, it is suggested that in patients with SVT, diagnostic methods for PM like the JAK2V617F mutation should be included.

Las neoplasias mieloproliferativas (NMP) son alteraciones crónicas de las células madre hematopoyéticas clonales caracterizadas por una mayor producción de granulocitos, glóbulos rojos o plaquetas. Una de las principales complicaciones de las NMP es la aparición de problemas trombóticos venosos y arteriales causados por un aumento en la agregación plaquetaria y la generación de trombina. Se evaluaron 11 casos de mielofibrosis primaria (MP), de los cuales dos debutaron con trombosis venosa esplácnica (TVE). Tras observar los resultados de este estudio y de la literatura mundial, se sugiere que al evaluar pacientes con TVE se incluyan métodos diagnósticos para MP, como la mutación JAK2V617F.

Residential water consumption, motivation for conserving water and the continuing tragedy of the commons.

This paper explores the effect of the perception of externalities (PE) on residential water consumption. Externalities occur when individuals make decisions that harm others, without concern for the impact or feeling a need to compensate for the harm. The aim of this study was to investigate whether PE affects people's motivation to conserve water, and, consequently, the practice of residential water consumption. Two hundred eighty Mexican citizens responded to a questionnaire investigating how they perceived that other individuals in their community wasted water. Respondents were also asked about their motives to conserve water, and direct observations of individual water consumption were recorded. Results were processed within a structural equations model, which revealed that motives to conserve water significantly inhibit water consumption. Since the perception of extemalities also inhibits conservation motives, the resulting effect of PE on water consumption is positive. This result means that the more people perceive that others waste water, the less their conservation motives, and, therefore, the more their own water consumption.

Plan administrativo para la creación del Instituto Nacional de Salud Ocupacional y Ambiental (INSOA): propuesta INSOA

Los objetivos de este informe son: garantizar las condiciones adecuadas de salud, higiene seguridad en el ambiente laboral. Lograr un ambiente de trabajo desprovisto de riesgos para la salud psicofísica de los trabajadores. Proteger a las personas y al medio ambiente en general contra los riesgos que directamente afectan a la salud, la seguridad y el equilibrio ecológico

Proyecto industrial .Licor de mandarina

El trabajo trata sobre la industrialización del li/ cor de mandarina teniendo como objetivo aprovechar una materia prima nacional que existe en nuestro pais en gran cantidad y que no se industrializa, la tecnología no es muy complicada, y se puede fabricar las maquinarias en nuestro pais abaratando asi los costos de fabricación