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Several Configurations (several + configuration)
Selected AbstractsOptical properties and transformation mechanism of oxygen centres and their aggregates in CaF2 crystalsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 1 2005A.S. Mysovsky Abstract Oxygen-vacancy dipoles and dimers in CaF2 crystals have been studied ab initio at DFT level and with the shell model using pair potentials. The calculated dipole reorientation barrier is 0.64 eV and the activation energy for diffusion of the dipoles is 1.61 eV. Optical absorption of O2, -VA dipole have been calculated with TD DFT and identified with experimental absorption bands, which appeared to have complex structure. The photodissociation mechanism of the dipole is discussed. Several configurations of the dimer (O2, -VA)2 were calculated. The association energy for the most favourable one is 0.48 eV. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] In Vitro and In Vivo Evaluation of Albumin Synthesis Rate of Porcine Hepatocytes in a Flat-Plate BioreactorARTIFICIAL ORGANS, Issue 7 2001Masaya Shito Abstract: Several configurations of extracorporeal bioartificial liver devices have been developed for the potential treatment of fulminant hepatic failure or as a bridge to liver transplantation. Recently, we developed a microchannel flat-plate bioreactor with an internal membrane oxygenator in which porcine hepatocytes are cultured as a monolayer on the bottom glass surface. In the present study, we investigated synthetic function of porcine hepatocytes in the bioreactor in both in vitro and in vivo flow circuit models. In vitro, albumin synthesis was stable in the bioreactor for up to 4 days of perfusion. In vivo, with the extracorporeal connection of the bioreactor to rat vasculature, porcine albumin was detectable for 24 h in the rat plasma. We also developed a simple mathematical model to predict the in vivo porcine albumin concentration in rat plasma. These results indicate that this configuration of a microchannel flat-plate bioreactor has potential as a liver support device and warrants further investigation. [source] Adaptable cache service and application to grid cachingCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 9 2010Laurent d'Orazio Abstract Caching is an important element to tackle performance issues in largely distributed data management. However, caches are efficient only if they are well configured according to the context of use. As a consequence, they are usually built from scratch. Such an approach appears to be expensive and time consuming in grids where the various characteristics lead to many heterogeneous cache requirements. This paper proposes a framework facilitating the construction of sophisticated and dynamically adaptable caches for heterogeneous applications. Such a framework has enabled the evaluation of several configurations for distributed data querying systems and leads us to propose innovative approaches for semantic and cooperative caching. This paper also reports the results obtained in bioinformatics data management on grids showing the relevance of our proposals. Copyright © 2009 John Wiley & Sons, Ltd. [source] Spherical sliding isolation bearings with adaptive behavior: Experimental verificationEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 2 2008Daniel M. Fenz Abstract This paper describes an experimental program to examine the force,displacement behavior of a class of multi-spherical sliding bearings. The primary goal of the experiments is to test the validity of the theory developed in a companion paper that describes the behavior of these devices. Experimental work consisted of testing the three primary variations of these bearings in several configurations of different friction and displacement capacities. Most tests were carried out at slow speeds; however, some testing was also conducted at high speed (up to approximately 400,mm/s) to examine the behavior under dynamic conditions. The results of experimental testing were generally found to be in very good agreement with the analytical results. It is shown that the forces and displacements at which transitions in stiffness occur are predictable and therefore controllable in design. Furthermore, the underlying principles of operation were confirmed by the fact that starting and stopping of sliding on the different surfaces occurred as expected from theory. Copyright © 2007 John Wiley & Sons, Ltd. [source] Characterization of image plates for neutron diffractionJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 5 2009Clive Wilkinson A method to measure the overall gain and point-spread function of an image-plate detector system (converter, phosphor, readout electronics) online from single-crystal diffraction patterns is derived. Only with a knowledge of these quantities can one estimate without bias the true standard deviations of the observed integrated intensities of Bragg reflections measured with such a detector. The gain corrected for the point-spread function should ideally be approximately 1.0 to avoid loss of data or precision due to the upper and lower limits of digitization of the diffraction patterns. The gain and the point-spread function are derived for several configurations of the three neutron Laue image-plate diffractometers, LADI, VIVALDI and LADI-III, at the Institut Laue,Langevin. The detective quantum efficiencies (DQE) of these instruments have been measured to be 0.16,(1), 0.57,(2) and 0.46,(3), respectively. It has also been found that the DQE is effectively constant for different times of exposure, despite the fading of the photostimulated luminescent signal during that time. While the results described in this paper concern neutron detection by image plates, the method is equally valid for other integrating detectors and radiations, e.g. CCD detectors and X-rays. [source] HRTEM of dislocation cores and thin-foil effects in metals and intermetallic compoundsMICROSCOPY RESEARCH AND TECHNIQUE, Issue 5 2006M.J. Mills Abstract Examples of the observation and analysis of dislocation cores and dislocation fine structure in metals and intermetallics using high resolution transmission electron microscopy are discussed. Specific examples include the 60° dislocations in aluminum, a,011, edge dislocations in NiAl, and screw dislocations in Ni3Al. The effect of the thin TEM foils on the structure and imaging of these dislocations is discussed in light of embedded atom method calculations for several configurations and coupled with image simulations. Some generalizations based on these calculations are discussed. These analyses enables determination of the spreading or decomposition of the edge component of the cores, both in and out of the glide plane, which can have significant implications for the modeling of macroscopic behavior. Microsc. Res. Tech. 69:317,329, 2006. © 2006 Wiley-Liss, Inc. [source] Electrodynamics in accelerated frames revisitedANNALEN DER PHYSIK, Issue 10 2010J.W. Maluf Abstract Maxwell's equations are formulated in arbitrary moving frames by means of tetrad fields, which are interpreted as reference frames adapted to observers in space-time. We assume the existence of a general distribution of charges and currents in an inertial frame. Tetrad fields are used to project the electromagnetic fields and sources on accelerated frames. The purpose is to study several configurations of fields and observers that in the literature are understood as paradoxes. For instance, are the two situations, (i) an accelerated charge in an inertial frame, and (ii) a charge at rest in an inertial frame described from the perspective of an accelerated frame, physically equivalent? Is the electromagnetic radiation the same in both frames? Normally in the analysis of these paradoxes the electromagnetic fields are transformed to (uniformly) accelerated frames by means of a coordinate transformation of the Faraday tensor. In the present approach coordinate and frame transformations are disentangled, and the electromagnetic field in the accelerated frame is obtained through a frame (local Lorentz) transformation. Consequently the fields in the inertial and accelerated frames are described in the same coordinate system. This feature allows the investigation of paradoxes such as the one mentioned above. [source] | |||||||||||||