Vast numbers of bronze coins have been, and continue to be, excavated from archaeological sites around the Greco-Roman world. While often of little value from a strictly numismatic point of view, these coins provide i...
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Vast numbers of bronze coins have been, and continue to be, excavated from archaeological sites around the Greco-Roman world. While often of little value from a strictly numismatic point of view, these coins provide invaluable data within their respective stratigraphic contexts and are used to date occupational and architectural phases more precisely than by ceramics alone. Unfortunately, the build-up of corrosion and mineralization on these coins during their centuries of burial often obscures their legends. Rather than employing potentially destructive and time-consuming chemical or mechanical cleaning techniques to reveal these features, commercially available Micro-focus X-Ray CT systems are now sufficiently well developed to reveal original surface features and to permit identification by a trained numismatist without any cleaning at all.
A model of phase-separation kinetics in systems exposed to energetic particle irradiation has been extended to include the effects of mobile dislocations. It is shown that when dislocations are allowed to participate ...
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A model of phase-separation kinetics in systems exposed to energetic particle irradiation has been extended to include the effects of mobile dislocations. It is shown that when dislocations are allowed to participate in the decomposition reaction, phase separation can occur at temperatures above the coherent spinodal, which is in agreement with several experiments on irradiated alloys. A linear stability analysis of the governing kinetic equations is performed and three regimes of microstructural evolution are identified within the parameter space of damage cascade size vs incident flux: complete phase separation, solid-solution behavior, and compositional patterning. In addition, numerical simulations of the evolving dislocation density and composition fields are performed. The numerical results provide the amplitude and wavelength of the stable patterns that can form under irradiation and elucidate the role of misfit dislocations in reducing the coherency strain due to atomic size mismatch.
When evolution plays a role, population dynamic models alone are not sufficient for determining the outcome of multi-species *** an expansion of Maynard Smith's concept of an evolutionarily stable strategy, evolut...
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This paper gives an overview of grid impact indicators that could be used to assess the impact of the energy exchange with a single intelligent building on the electricity grid. Seven indicators are given, the capacit...
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This paper gives an overview of grid impact indicators that could be used to assess the impact of the energy exchange with a single intelligent building on the electricity grid. Seven indicators are given, the capacity factor, loss of load probability, cover factor, one percent peak power, peaks above limit, dimensioning rate and kVA credit. An example of a building simulation is used to show what these indicators can teach us. For this example the indicators are calculated and an explanation of what they show is given. Finally a summary of the grid impact indicators is given in the conclusion of this paper.
We numerically simulate the hemodynamics of aneurysmal flow and evaluate stent design configuration based on an idealistic geometrical model. We examined large-scale swirling of blood within a significantly dilated an...
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We numerically simulate the hemodynamics of aneurysmal flow and evaluate stent design configuration based on an idealistic geometrical model. We examined large-scale swirling of blood within a significantly dilated aneurysm. Various parameters such as stent porosity and strut shape have an impact on the pressure and shear strain rate within the aneurysm. Using biofluid mechanical parameters such as pressure gradient and shear strain rate for aneurysmal arteries implanting with different stent configuration, a flow analysis framework for evaluation of stents is developed. With the application of cardiac flow analysis, we are aim to achieve a balance in the two properties in order to prevent aneurysmal rupture and thrombosis formation and give out the most suitable stent configuration for the stent implanting surgery.
In this chapter, the considered issue is presented on the base of two different models of plasticity theory and the detailed derivation of formulae for the average normalised axial stress in the minimal section plane ...
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In this chapter, the methods utilised to determine the mechanical material properties are presented. In addition, the static tensile test is characterised taking into account the material constants obtained from the e...
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The axisymmetric specimen applied in the tensile test is numerically characterised within this chapter. Subsequently, the simplifying assumptions of the classical approaches are verified utilising the results obtained...
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In the present study, the evolution of micromagnetic structure and microstructure is studied in-situ both as a function of temperature and applied magnetic field, using single crystal Fe-Pd and Ni-Mn-Ga Heusler alloys...
In the present study, the evolution of micromagnetic structure and microstructure is studied in-situ both as a function of temperature and applied magnetic field, using single crystal Fe-Pd and Ni-Mn-Ga Heusler alloys. Through the development of a novel technique called ‘Magnetic Transition Spectrum’ to study temperature dependent domain dynamics, the relative sequence of micromagnetic reconfiguration with respect to the martensitic transformation has been determined for the first time. Results show that the FSMAs may be viewed as magnetic mosaics, a new perspective, which is also more amenable to modeling the physical properties of these alloys. Finally, the concept of magnetic mosaics has been used to synthesize a novel class of materials with engineered magnetic anisotropies, and is briefly discussed.
Single crystal SmMnO3 has been grown by the floating-zone method. We have measured the magnetization and specific heat in magnetic fields oriented along three principal crystal axes of precisely oriented single crysta...
Single crystal SmMnO3 has been grown by the floating-zone method. We have measured the magnetization and specific heat in magnetic fields oriented along three principal crystal axes of precisely oriented single crystals. Below TN of the Mn3+-ion array, the magnetic moments of the Sm3+ ions are progressively oriented antiparellel to the weak canted-spin ferromagnetic moment of the antiferromagnetic (AF) Mn3+-ion array due to an internal exchange field Hin ∥ c. On cooling through a compensation temperature Tcomp ≈ 9 K, the dominant moment parallel to c changes from the canted-spin Mn3+ ions to the Sm3+ moments. A spin reversal in an Hc ≥ 1 T changes the magnetic field splitting of the Kramers doublet on the Sm3+ ions from Hin − Hc to Hin + Hc, where Hc is a field applied along the c axis. This change, monitored by the Schottky contribution to the specific heat, creates an abrupt change at Tt = Tcomp ± δ. We have found no evidence that the transition at Tt is first-order despite its abrupt nature.
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