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1.
In this paper, an adaptive FE analysis is presented based on error estimation, adaptive mesh refinement and data transfer for enriched plasticity continua in the modelling of strain localization. As the classical continuum models suffer from pathological mesh-dependence in the strain softening models, the governing equations are regularized by adding rotational degrees-of-freedom to the conventional degrees-of-freedom. Adaptive strategy using element elongation is applied to compute the distribution of required element size using the estimated error distribution. Once a new mesh is generated, state variables and history-dependent variables are mapped from the old finite element mesh to the new one. In order to transfer the history-dependent variables from the old to new mesh, the values of internal variables available at Gauss point are first projected at nodes of old mesh, then the values of the old nodes are transferred to the nodes of new mesh and finally, the values at Gauss points of new elements are determined with respect to nodal values of the new mesh. Finally, the efficiency of the proposed model and computational algorithms is demonstrated by several numerical examples.  相似文献   
2.
We consider the rate of convergence for a class of perturbed hemivariational inequalities in reflexive Banach Spaces. Our results can be viewed as an extension and refinement of some previous known results in this area.  相似文献   
3.
The ability of living filamentous cells of the cyanobacterium Oscillatoria homogenea to separate stable strontium and 90Sr from aqueous solution is demonstrated in this study. On a basis of filamentous cell biovolume, the removal were 43.78 nM·ml·(mm3)−1 and 3129.48 mBq·ml·(mm3)−1 after 240 hour incubation. The optimum pH for strontium uptake is 9±0.3. The increasing biovolume of the blue-green alga elevates sorption. In the liquid culture containing 21.2 mm3·ml−1 filamentous cells and 1000 nM·ml−1 initial strontium concentration, the maximum strontium removal was 455.34 nM·ml·(mm3)−1. At 1200 Lux illumination, the maximum removal value was 58.62 nM·ml·(mm3)−1, and at the initial strontium concentration of 6590 nM·ml−1, 235.40 nM·ml·(mm3)−1 removal was observed. The experimental data fitted to Langmuir isotherm and the model parameters and correlation coefficient (R 2) were q max = 7.143 μg·(mm3)−1, b = 0.003 and 0.99, respectively.  相似文献   
4.
In this paper we prove the existence of solutions of the generalized vector equilibrium problem in the setting of Hausdorff topological vector spaces. As applications, we present some relevant particular cases: a generalized vector variational-like inequality in Hausdorff topological vector spaces, and equilibrium problem in the case of pseudomonotone real functions, and a generalized weak Pareto optima problem.  相似文献   
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Functionalized 4-nitro- and 4-aminophenols were regioselectively prepared based on [3+3] cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-ethoxy-2-nitro-2-en-1-ones.  相似文献   
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The formal [3+3] cyclization of 1,3-bis(silyloxy)-1,3-butadienes with readily available 2-arylsulfonyl-3-ethoxy-2-en-1-ones resulted in regioselective formation of 4-(arylsulfonyl)phenols.  相似文献   
9.
The subject of the title is briefly discussed and clarified based on the available experimental evidence.  相似文献   
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