1000 resultados para Ceramic red
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Poster presentado en Society for Post-Medieval Archaeology Conference, in St John's, Newfoundland,(Canadá)(June 2010)
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Peel test measurements and inverse analysis to determine the interfacial mechanical parameters for the metal film/ceramic system are performed, considering that there exist an epoxy interface layer between film and ceramic. In the present investigation, Al films with a series of thicknesses between 20 and 250 mu m and three peel angles of 90, 135 and 180 degrees are considered. A finite element model with the cohesive zone elements is used to simulate the peel test process. The finite element results are taken as the training data of a neural network in the inverse analysis. The interfacial cohesive energy and the separation strength can be determined based on the inverse analysis and peel experimental result. (C) 2008 Elsevier Ltd. All rights reserved.
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The materials considered in our analysis were ZrB2 ceramic matrix composites. Effect of two different additives (graphite and AlN) on thermal shock stability for the materials was measured by water quench test. It showed that it may provide more stable thermal shock properties with additives of graphite. It was explained by different thermal properties and crack resistance of the two materials in detail. Surface oxidation was one of main reasons for strength degradation of ceramic with additives of graphite after quenched in water, and surface crack was one of main reasons for strength degradation of ceramic with additives of AlN after quenched in water. It was presented that it was a potential method for improving thermal shock stability of ZrB2 ceramic matrix composites by introducing proper quantities of graphite.
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In this paper, multi-hole cooling is studied for an oxide/oxide ceramic specimen with normal injection holes and for a SiC/SiC ceramic specimen with oblique injection holes. A special purpose heat transfer tunnel was designed and built, which can provide a wide range of Reynolds numbers (10(5)similar to 10(7)) and a large temperature ratio of the primary flow to the coolant (up to 2.5). Cooling effectiveness determined by the measured surface temperature for the two types of ceramic specimens is investigated. It is found that the multi-hole cooling system for both specimens has a high cooling efficiency and it is higher for the SiC/SiC specimen than for the oxide/oxide specimen. Effects on the cooling effectiveness of parameters including blowing ratio, Reynolds number and temperature ratio, are studied. In addition, profiles of the mean velocity and temperature above the cooling surface are measured to provide further understanding of the cooling process. Duplication of the key parameters for multi-hole cooling, for a representative combustor flow condition (without radiation effects), is achieved with parameter scaling and the results show the high efficiency of multi-hole cooling for the oblique hole, SiC/SiC specimen. (C) 2008 Elsevier Ltd. All rights reserved.
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Durante los últimos años hemos venido observando la tendencia a incorporar capacidad de proce- samiento y comunicación a dispositivos que hasta entonces se utilizaban de modo independiente. La evolución de los móviles a smartphones es un claro ejemplo de dicha tendencia, aunque también cabe mencionar otros ejemplos, como es el caso de los denominados hogares inteligentes, en los que elementos del hogar se encuentran interconectados y pueden actuar de modo conjunto. Esta ten- dencia no se limita a sistemas independientes, sino que propone interconectar todos los elementos disponibles para conformar la denominada Internet de los Objetos/Cosas o Internet of Things, IoT. Una de las mayores dificultades que se presenta en estos sistemas es que las características de es- tos nuevos dispositivos inteligentes, en general limitados en términos de cómputo, almacenamiento, autonomía o comunicación, queda a menudo lejos de los equipos informáticos tradicionales. Esta cuestión, junto con la ausencia de estándares para gestionar estos dispositivos, constituye un impor- tante problema a abordar. Considerando este marco, en este proyecto se ha desarrollado una aplicación orientada a este tipo de dispositivos. Más concretamente, la aplicación tiene como soporte una red de sensores inalámbricos, WSN, con el objetivo de realizar seguimiento de individuos. Cabe destacar que el desarrollo de la aplicación se ha realizado utilizando Contiki OS, sistema ope- rativo diseñado especialmente para dispositivos con características limitadas como los presentados anteriormente y firme candidato a convertirse en estándar.
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El seguimiento de distintas especies de animales contribuye en gran medida a su estudio y, por tanto, a su conservación y control. Los avances tecnológicos de los últimos años han facilitado las posibilidades de seguimiento con la creación de distintos dispositivos que permiten conocer los movimientos de la especie que se desea estudiar. Uno de los sistemas más utilizados consiste en la utilización de dispositivos GPS incorporados al espécimen sobre el que se realiza el seguimiento y cuya señal es recogida por satélites que se encargan de almacenar y posteriormente reenviar la información para su almacenamiento y procesamiento en el laboratorio. El principal problema de este sistema es su elevado coste. Existen alternativas que no presentan un coste tal alto, tales como el uso de módulos basados en telefonía móvil. Sin embargo, tienen limitaciones de cobertura, por lo que no es aplicable en todos los ámbitos. Este proyecto forma parte de una propuesta que ofrece realizar seguimiento de ejemplares de una especie de ave, la gaviota Patiamarilla, en Gipuzkoa mediante la utilización de una red de sensores y que tiene varias ventajas frente a las opciones presentadas anteriormente. En este proyecto en concreto se ha diseñado e implementado el módulo que permite recoger la información obtenida por el conjunto de sensores (cada ejemplar lleva incorporado un sensor que permite registrar su posición) y enviarla a un servidor centralizado para su posterior consulta y análisis. Adicionalmente, también se permite consultar el último estado registrado de cada dispositivo de seguimiento, además de contemplar la posibilidad de actualizar su software.
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Red-shift conical emission (CE) is observed by femtosecond laser pulse propagating in BK7 at a low input power (compared to those input powers for generation of blue-shift CE). With the increasing input power the blue-shift CE begins to appear whereas the red-shift CE ring (902 nm in our experiment) disappears accompanied by the augment of the central white spot size synchronously. The disappearing of red-shift CE in our experiment is explained such that the increase of axial intensity is much higher than that of ring emission and the augment of the central white spot size with the increasing input laser power.
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The characteristics of backward harmonic radiation due to electron oscillations driven by a linearly polarized fs laser pulse are analysed considering a single electron model. The spectral distributions of the electron's backward harmonic radiation are investigated in detail for different parameters of the driver laser pulse. Higher order harmonic radiations are possible for a sufficiently intense driving laser pulse. We have shown that for a realistic pulsed photon beam, the spectrum of the radiation is red shifted as well as broadened because of changes in the longitudinal velocity of the electrons during the laser pulse. These effects are more pronounced at higher laser intensities giving rise to higher order harmonics that eventually leads to a continuous spectrum. Numerical simulations have further shown that by increasing the laser pulse width the broadening of the high harmonic radiations can be controlled.
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The effect of alcohol solution on single human red blood Cells (RBCs) was investigated using near-infrared laser tweezers Raman spectroscopy (LTRS). In our system, a low-power diode laser at 785 nm was applied for the trapping of a living cell and the excitation of its Raman spectrum. Such a design could simultaneously reduce the photo-damage to the cell and suppress the interference from the fluorescence on the Raman signal. The denaturation process of single RBCs in 20% alcohol solution was investigated by detecting the time evolution of the Raman spectra at the single-cell level. The vitality of RBCs was characterized by the Raman band at 752 cm(-1), which corresponds to the porphyrin breathing mode. We found that the intensity of this band decreased by 34.1% over a period of 25 min after the administration of alcohol. In a further study of the dependence of denaturation on alcohol concentration, we discovered that the decrease in the intensity of the 752 cm(-1) band became more rapid and more prominent as the alcohol concentration increased. The present LTRS technique may have several potential applications in cell biology and medicine, including probing dynamic cellular processes at the single cell level and diagnosing cell disorders in real time. Copyright (c) 2005 John Wiley T Sons, Ltd.
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[ES]El proyecto está orientado a conseguir una comunicación inalámbrica y segura de una red de sensores IP. Por un lado, mediante el protocolo 6LoWPAN se consigue que los datos se transmitan mediante IPv6 y, por otro lado, gracias al protocolo LADON se establecen los servicios de seguridad de autenticación, integridad de datos, autorización y control de acceso.
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Red fluorescent proteins (RFPs) have attracted significant engineering focus because of the promise of near infrared fluorescent proteins, whose light penetrates biological tissue, and which would allow imaging inside of vertebrate animals. The RFP landscape, which numbers ~200 members, is mostly populated by engineered variants of four native RFPs, leaving the vast majority of native RFP biodiversity untouched. This is largely due to the fact that native RFPs are obligate tetramers, limiting their usefulness as fusion proteins. Monomerization has imposed critical costs on these evolved tetramers, however, as it has invariably led to loss of brightness, and often to many other adverse effects on the fluorescent properties of the derived monomeric variants. Here we have attempted to understand why monomerization has taken such a large toll on Anthozoa class RFPs, and to outline a clear strategy for their monomerization. We begin with a structural study of the far-red fluorescence of AQ143, one of the furthest red emitting RFPs. We then try to separate the problem of stable and bright fluorescence from the design of a soluble monomeric β-barrel surface by engineering a hybrid protein (DsRmCh) with an oligomeric parent that had been previously monomerized, DsRed, and a pre-stabilized monomeric core from mCherry. This allows us to use computational design to successfully design a stable, soluble, fluorescent monomer. Next we took HcRed, which is a previously unmonomerized RFP that has far-red fluorescence (λemission = 633 nm) and attempted to monomerize it making use of lessons learned from DsRmCh. We engineered two monomeric proteins by pre-stabilizing HcRed’s core, then monomerizing in stages, making use of computational design and directed evolution techniques such as error-prone mutagenesis and DNA shuffling. We call these proteins mGinger0.1 (λem = 637 nm / Φ = 0.02) and mGinger0.2 (λem = 631 nm Φ = 0.04). They are the furthest red first generation monomeric RFPs ever developed, are significantly thermostabilized, and add diversity to a small field of far-red monomeric FPs. We anticipate that the techniques we describe will be facilitate future RFP monomerization, and that further core optimization of the mGingers may allow significant improvements in brightness.
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Cases of red colouration in small lake basins, due to the abundant appearance of microorganisms have long been known. Usually it is caused by a fast, sudden, intensive propagation (so called ”bloom”) of Cyanophycae and bacteria. (e.g. Oscillatoracae, thiobacteria etc.). An exception to this is the red colouration of Tovel-See, an alpine lake basin in the Dolomites of the Brenta group (Trentino), lying at a height of 1178 m and hidden in the woodland of a valley. Here the red bloom has a double rhythm: a daily and a yearly rhythm. The colouration of one part of the lake takes place in the warmest months of the year (i.e. July, August, September) and in the middle hours of the day. The immediate origin of the bloom has been known for a long time: it is caused by the Peridinacae Glenodinium sanguineum. This paper describes the phenomenon of red colouration of the lake and discusses its conditions.