Relationship between solidification microstructure and hot cracking susceptibility for continuous casting of low-carbon and high-strength low-alloyed steels: A phase-field study

© The Minerals, Metals & Materials Society and ASM International 2013Hot cracking is one of the major defects in continuous casting of steels, frequently limiting the productivity. To understand the factors leading to this defect, microstructure formation is simulated for a low-carbon and two high-strength low-alloyed steels. 2D simulation of the initial stage of solidification is performed in a moving slice of the slab using proprietary multiphase-field software and taking into account all elements which are expected to have a relevant effect on the mechanical properties and structure formation during solidification. To account for the correct thermodynamic and kinetic properties of the multicomponent alloy grades, the simulation software is online coupled to commercial thermodynamic and mobility databases. A moving-frame boundary condition allows traveling through the entire solidification history starting from the slab surface, and tracking the morphology changes during growth of the shell. From the simulation results, significant microstructure differences between the steel grades are quantitatively evaluated and correlated with their hot cracking behavior according to the Rappaz-Drezet-Gremaud (RDG) hot cracking criterion. The possible role of the microalloying elements in hot cracking, in particular of traces of Ti, is analyzed. With the assumption that TiN precipitates trigger coalescence of the primary dendrites, quantitative evaluation of the critical strain rates leads to a full agreement with the observed hot cracking behavior. © 2013 The Minerals, Metals & Materials Society and ASM International

Crab Cavity and Cryomodule Development for HL-LHC

The HL-LHC project aims at increasing the LHC luminosity by a factor 10 beyond the design value. The installation of a set of RF Crab Cavities to increase bunch crossing angle is one of the key upgrades of the program. Two concepts, Double Quarter Wave (DQW) and RF Dipole (RFD) have been proposed and are being produced in parallel for test in the SPS beam before the next long shutdown of CERN accelerator’s complex. In the retained concept, two cavities are hosted in one single cryomodule, providing thermal insulation and interfacing with RF coupling, tuning, cryogenics and beam vacuum. This paper overviews the main design choices for the cryomodule and its different components, which have the goal of optimizing the structural, thermal and electro-magnetic behavior of the system, while respecting the existing constraints in terms of integration in the accelerator environment. Prototyping and testing of the most critical components, manufacturing, preparation and installation strategies are also described

A study of asymmetric tensile properties of large area GEM foil

Gas Electron Multiplier (GEM) technology is being used in various applications, particularly in high energy physics experiments. The GEM is known as a reliable detector in high radiation environment which can maintain high temporal and position resolution. GEM foil is the basic part of the detector which consists of a composite material (polyimide and copper). Large size GEM foil has complex mechanical structure and asymmetries which mainly arises due to formation of the HV sectors in the foil. These asymmetries become very relevant when large size foils are stretched to build a detector. In this article asymmetry affects are presented that define the tensile properties of a large size segmented GEM foil

Total nutritional therapy : a nutrition education program for physicians

Objetivo: Casi la mitad de todos los pacientes hospitalizados se encuentran desnutridos y los médicos tienen muy poco conocimiento o apenas utilizan el soporte nutricional1. Para corregir este problema, la Federación Latinoamericana de Nutrición Parenteral y Enteral (FELANPE) ideó un curso introductorio de nutrición clínica para médicos de dos días, con el apoyo de los Laboratorios Abbott. El objetivo del tratamiento nutricional total (TNT) es ayudar al médico a aprovechar sus conocimientos de nutrición para incrementar la conciencia sobre malnutrición y aplicación del tratamiento nutricional. Desde 1997, más de 8.000 médicos han completado el curso TNT en 16 países latinoamericanos. Métodos y procedimientos experimentales: Durante 1999 y 2000, 675 participantes respondieron, seis meses después de haber terminado el curso TNT, a una encuesta en la que se pretendía averiguar la repercusión que había tenido el curso en el uso de la evaluación nutricional, los equipos de apoyo nutricional o las consultas sobre nutrición en la práctica clínica y si habían participado en alguna asociación o conferencia de nutrición. Resultados: La mayoría de los médicos que rellenaron la encuesta había aumentado el uso de las herramientas de evaluación nutricional y el tiempo dedicado a este tratamiento; asimismo, había aumentado el número de pacientes que recibieron tratamiento nutricional. Conclusiones: El curso TNT ha resultado un modelo eficiente para la educación de los médicos generales en nutrición clínica. Este curso debería integrarse en la formación de los médicos residentes.Q4Q3Objective: Almost half of all hospitalized patients are malnourished with low physician awareness or implementation of nutrition support1. To address this problem, a 2-day immersion course in clinical nutrition for physicians was developed by the Latin American Federation of Parenteral and Enteral Nutrition (FELANPE) with support from Abbott Laboratories. The goal of Total Nutritional Therapy (TNT) is to help physicians utilize this nutrition knowledge to increase their awareness of malnutrition and implementation of nutritional therapy. Since 1997, over 8,000 physicians have completed the TNT course in 16 Latin American countries. Research Methods & Procedures: During 1999 and 2000, 675 participants responded to a survey 6 months after having completed the TNT course to determine what impact the course had on the use of nutrition assessment, nutrition support teams, or nutrition consultations in their clinical practice, and if they had participated in any nutrition association or conferences. Results: The majority of physicians who completed the survey increased their use of nutrition assessment and time dedicated to nutrition therapy, and increased the number of their patients placed on nutrition therapy. Conclusions: The TNT course has been shown to be an efficient model of clinical nutrition education for general physicians. The course should be considered as part of the training of medical residents.https://orcid.org/0000-0003-0401-0743N/

Deformability Tests of Pure Niobium

research team at the University of Miskolc's Faculty of Materials Science and Technology has signed a cooperation agreement with the Geneva-based European Organization for Nuclear Research (CERN) for testing of the materials employed in the Crab Cavities will be installed in the next generation of the LHC (the so-called High Luminosity Large Hadron Collider – HL-LHC). At the University of Miskolc, high purity niobium rolling experiments were carried out in conventional (unidirectional) and cross-rolled manners in order to increase the deep drawability of the final sheet. The deformability of niobium was measured by Watts- Ford and compression tests. The microstructure and anisotropy (texture) results of the initial material and the straight-rolled products are reported

Design of Dressed Crab Cavities for the HL-LHC Upgrade

The HL-LHC upgrade relies on a set of RF crab cavities for reaching its goals. Two parallel concepts, the Double Quarter Wave (DQW) and the RF Dipole (RFD), are going through a comprehensive design process along with preparation of fabrication in view of extensive tests with beam in SPS. High Order Modes (HOM) couplers are critical in providing damping in RF cavities for operation in accelerators. HOM prototyping and fabrication have recently started at CERN. In this paper, an overview of the final geometry is provided along with an insight in the mechanical and thermal analyses performed to validate the design of this critical component. Emphasis is also given to material selection, prototyping, initial fabrication and test campaigns that are aimed at fulfilling the highly demanding tolerances of the couplers

Quality and Safety Aspects of Infant Nutrition

Quality and safety aspects of infant nutrition are of key importance for child health, but oftentimes they do not get much attention by health care professionals whose interest tends to focus on functional benefits of early nutrition. Unbalanced diets and harmful food components induce particularly high risks for untoward effects in infants because of their rapid growth, high nutrient needs, and their typical dependence on only one or few foods during the first months of life. The concepts, standards and practices that relate to infant food quality and safety were discussed at a scientific workshop organized by the Child Health Foundation and the Early Nutrition Academy jointly with the European Society for Paediatric Gastroenterology, Hepatology and Nutrition, and a summary is provided here. The participants reviewed past and current issues on quality and safety, the role of different stakeholders, and recommendations to avert future issues. It was concluded that a high level of quality and safety is currently achieved, but this is no reason for complacency. The food industry carries the primary responsibility for the safety and suitability of their products, including the quality of composition, raw materials and production processes. Introduction of new or modified products should be preceded by a thorough science based review of suitability and safety by an independent authority. Food safety events should be managed on an international basis. Global collaboration of food producers, food-safety authorities, paediatricians and scientists is needed to efficiently exchange information and to best protect public health. Copyright (C) 2012 S. Karger AG, Base

Caracterización de la púrpura trombótica trombocitopénica congénita mediante técnicas inmunológicas y moleculares: resultados de la colección nacional del GEPTT

CO-093 Introducción: La Púrpura Trombótica Trombocitopénica congénita (PTTc) es una enfermedad ultra-rara caracterizada por un déficit severo de la enzima ADAMTS13 como consecuencia de mutaciones heredadas de forma autosómica recesiva en el gen ADAMTS13 (9q34). En este estudio, desarrollado dentro del Grupo Cooperativo Español de PTT (GEPTT), se ha llevado a cabo la creación de una colección centralizada de muestras biológicas y su caracterización inmunológica y molecular para mejorar el diagnóstico y el manejo clínico de los pacientes. Métodos: Se incluyeron en este estudio seis pacientes con diagnóstico clínico o sospecha de PTTc de diferentes hospitales españoles. Se estudió la actividad de ADAMTS13 e inhibidores mediante la técnica ELISA con el kit “TECHNOZYM® ADAMTS-13 Activity e INH” (Technoclone). Además, se realizó test Bethesda para descartar la presencia de inhibidores no IgG. Para el estudio genético, se implementó un panel de captura (SureSelect, Agilent) dirigido a la región genómica completa, incluyendo también las regiones no codificantes, del gen ADAMTS13 (chr9: 136278459 - 136325025, hg19). Las librerías de DNA se secuenciaron con la plataforma MiSeq (Illumina®) y el posible efecto patogénico de las variantes identificadas se estudió a nivel de i) proteína, utilizando predictores de cambio de aminoácido (SIFT) y de estructura de la proteína (SwissModel) y ii) splicing, con herramientas de análisis in silico (HSF) y validación funcional in vitro mediante minigenes. En 3 casos se realizó un cariotipo molecular utilizando array de SNPs (CytoScan HD, Affymetrix) para detectar regiones de pérdida de material genético y/o de heterocigosidad (LOH). Resultados: La mediana de actividad de ..