Pitting Corrosion in Austenitic Stainless Steel Water Tanks of Hotel Trains

The water storage tanks of hotel trains suffered pitting corrosion. To identify the cause, the tanks were subjected to a detailed metallographic study and the chemical composition of the austenitic stainless steels used in their construction was determined. Both the tank water and the corrosion products were further examined by physicochemical and microbiological testing. Corrosion was shown to be related to an incompatibility between the chloride content of the water and the base and filler metals of the tanks. These findings formed the basis of recommendations aimed at the prevention and control of corrosion in such tanks. Se han detectado problemas de corrosión por picaduras en los depósitos de agua de trenes hotel. Para identificar las causas se llevó a cabo un detallado estudio metalográfico así como de la composición química de los aceros inoxidables austeníticos utilizados en su construcción. También se realizaron estudios fisicoquímicos y microbiológicos de los productos de corrosión. Se ha encontrado que los problemas de corrosión están relacionados con la incompatibilidad entre el contenido en cloruros del agua y los metales base y de aporte de la soldadura de los tanques. En base a estos hallazgos se proponen una serie de recomendaciones encaminadas a la prevención y control de la corrosión de dichos depósitos

Boundary Effects in the Eigenstrain Method

We present a comprehensive study of the effects of internal boundaries on the accuracy of residual stress values obtained from the eigenstrain method. In the experimental part of this effort, a composite specimen, consisting of an aluminum cylinder sandwiched between steel cylinders of the same diameter, was uniformly heated under axial displacement constraint. During the experiment, the sample temperature and the reaction stresses in the load frame in response to changes in sample temperature were monitored. In addition, the local (elastic) lattice strain distribution within the specimen was measured using neutron diffraction. The eigenstrain method, utilizing finite element modeling, was then used to predict the stress field existing within the sample in response to the constraint imposed by the load frame against axial thermal expansion. Our comparison of the computed and measured stress distributions showed that, while the eigenstrain method predicted acceptable stress values away from the cylinder interfaces, its predictions did not match experimentally measured values near them. These observations indicate that the eigenstrain method is not geometry-independent, or valid for all sample geometries

Global trends of habitat destruction and consequences for parrot conservation

Human advance on natural habitats is a major cause of biodiversity loss. This transformation process represents a profound change in wooded environments, disrupting original communities of flora and fauna. Many species are highly dependent on forests, especially parrots (Psittaciformes) with almost a third of their species threatened by extinction. Most parrot species occur in tropical and subtropical forests, and given the forest dependence of most species, this is the main reason why habitat loss has been highlighted as the main threat for the group. Such habitat loss acts in synergy with other important threats (e.g., logging and poaching), which become especially problematic in certain developing countries along tropical latitudes. In this study, we used available information on parrot distributions, species traits, IUCN assessment, habitat loss and timber extraction for different periods, and distribution of protected areas, to determine conservation hotspots for the group, and analyze potential changes in the conservation status of these species. We detected four conservation hotspots for parrots: two in the Neotropics and two in Oceania, all of them facing different degrees of threat in regard of current habitat loss and agricultural trends. Our results suggest that the future of the group is subject to policymaking in specific regions, especially in the northeastern Andes and the Atlantic Forest. In addition, we predicted that agricultural expansion will have a further negative effect on the conservation status of parrots, pushing many parrot species to the edge of extinction in the near future. Our results have conservation implications by recommending protected areas in specific parrot conservation hotspots. Our recommendations to mitigate conservation risks to this group of umbrella species would also benefit many other coexisting species as well.Fil: Vergara Tabares, David Lautaro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Zoología Aplicada; ArgentinaFil: Cordier, Javier Maximiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Zoología Aplicada; ArgentinaFil: Landi, Marcos Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Zoología Aplicada; ArgentinaFil: Olah, George. Wildlife Messengers; Estados UnidosFil: Nori, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Zoología Aplicada; Argentin

Life cycle assessment of regional brick manufacture

This document presents a Life Cycle Assessment (LCA) study to quantify the environmental cradle-to-gate impact of the manufacture of brick for the construction industry, produced with material of igneous source. Its mineral composition and thermal isolation properties were characterized for use in real estate construction. The LCA results for brick manufacture using this material identified the greatest environmental impact to be associated with material extraction and its proportional cement content. Additionally, this document presents an evaluation of the environmental impact of the manufacturing process by comparing traditional fired clay brick and brick of the material under study. In conclusion, the studied material shows thermal insulation qualities and suitability for the manufacture of bricks with low incorporated energy.<br><br>Este trabajo presenta un estudio de Análisis de Ciclo de Vida (ACV) para cuantificar los impactos ambientales de la cuna a la puerta de la manufactura de ladrillos para la industria de la construcción, fabricados de un material de origen ígneo. Se caracterizó su composición mineralógica y propiedades de aislamiento térmico para ser usado en la construcción de inmuebles. Los resultados ACV de la fabricación de ladrillos de este material, identificaron la mayor contribución a los impactos ambientales asociados a la extracción del material y la cantidad proporcional de cemento. Adicionalmente, se presenta una evaluación comparativa del impacto ambiental entre la manufactura de un ladrillo tradicional de arcilla cocido y de un ladrillo del material en estudio. En conclusión el material estudiado muestra cualidades de aislamiento térmico y es adecuado para la fabricación de ladrillos con baja energía incorporada

Wireless Underground Channel Modeling

A comprehensive treatment of wireless underground channel modeling is presented in this chapter. The impacts of the soil on bandwidth and path loss are analyzed. A mechanism for the UG channel sounding and multipath characteristics analysis is discussed. Moreover, novel time-domain impulse response model for WUC is reviewed with the explanation of model parameters and statistics. Furthermore, different types of the through-the-soil wireless communications are surveyed. Finally, the chapter concludes with discussion of the UG wireless statistical model and path loss model for through-the-soil wireless communications in decision agriculture. The model presented in this chapter is also validated with empirical data

A review of composite product data interoperability and product life-cycle management challenges in the composites industry

A review of composite product data interoperability and product life-cycle management challenges is presented, which addresses “Product Life-cycle Management”, developments in materials. The urgent need for this is illustrated by the life-cycle management issues faced in modern military aircraft, where in-service failure of composite parts is a problem, not just in terms of engineering understanding, but also in terms of the process for managing and maintaining the fleet. A demonstration of the use of ISO 10303-235 for a range of through-life composite product data is reported. The standardization of the digital representation of data can help businesses to automate data processing. With the development of new materials, the requirements for data information models for materials properties are evolving, and standardization drives transparency, improves the efficiency of data analysis, and enhances data accuracy. Current developments in Information Technology, such as big data analytics methodologies, have the potential to be highly transformative

Optimization of PCR conditions to amplify microsatellite loci in the bunchgrass lizard (Sceloporus slevini) genomic DNA

<p>Abstract</p> <p>Background</p> <p>Microsatellites, also called Simple Sequence Repeats (SSRs), repetitions of nucleotide motifs of 1-5 bases, are currently the markers of choice due to their abundant distribution in the genomes, and suitability for high-throughput analysis. A total of five different primer pairs were optimized for polymerase chain reaction (PCR) to amplify microsatellite loci in total genomic DNA of bunchgrass lizards (<it>Sceloporus slevini</it>) collected from three sites in southeastern Arizona; the Sonoita Plain, Chiricahua Mountains and Huachuca Mountains.</p> <p>Findings</p> <p>The primers used for current investigation were originally designed for the Eastern Fence Lizard (<it>Sceloporus undulatus</it>). Five primer pairs were selected based on annealing temperatures for optimizing the PCR conditions to amplify with bunchgrass lizards. Different concentrations of DNA and annealing temperature were optimized. While keeping other reagents constant, a DNA concentration, 37.5 ng in the final reaction volume and PCR conditions of an initial denaturation of 94°C for five minutes, an annealing temperature of 55°C and final extension of 72°C for four minutes gave the best amplification for all the primer pairs.</p> <p>Conclusions</p> <p>Modifying the standard protocol for annealing temperatures and final extension time increases the success of cross amplification of specific microsatellite loci in the bunchgrass lizard. A loading volume of 5 ul DNA at a concentration of 10 ng/ul and a 2% agarose for gel electrophoresis were observed the best for cross amplification of selected five primer pairs on bunch grass lizard.</p> <p>Trial Registration</p> <p>The research was conducted with Arizona Game and Fish Department scientific collecting permits SP565256, SP657407 & SP749119 to Dr. Christian A d'Orgeix.</p

Influence of high-dose gamma radiation and particle size on antioxidant properties of Maize ( Zea mays L.) flour

ABSTRACT Influence of high-dose gamma radiation and particle size on antioxidant properties of maize (Zea mays L.) flour was studied using response surface methodology. A central composite design based on three levels of each of particle size, in terms of mesh number (40, 60 and 80 meshes), and gamma radiation dose (25, 50 and 75 kGy) was constructed. A statistically significant dose-dependent decrease (p<0.05) in antioxidant properties of gamma irradiated flour was observed. However, an increase in the mesh number (decrease in particle size of flour) resulted in an increase in antioxidant properties. The optimum level of radiation dose to achieve maximum value of responses was found to be 50 kGy for Trolox equivalent total antioxidant activity (TETAOA), 25 kGy for iron chelating ability (ICA), 25 kGy for reducing power (RP) and 75 kGy for linoleic acid reduction capacity (LARC). However, the optimum level of mesh number to achieve desired levels of TETAOA, ICA, RP and LARC was found to be 80 meshes