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Wide bandgap II–VI semiconductor quantum dots embedded in glass matrix have shown great potential for opto-electronic device applications. The current problem is to achieve low size dispersion, high volume fraction, and better control over the size of the quantum dots in glass matrix. In this work, a modified growth method has been proposed to achieve a greater control over the size of quantum dots, to reduce their size dispersion and to increase their volume fraction. A theoretical model has been developed to quantitatively estimate the various parameters of the quantum dots. The effects of aging on various parameters of quantum dots in Semiconductor-Doped Glass (SDG) samples have also been discussed in the present work.

Different time-dependent mechanisms such as creep, environmental surface oxidation or internal material degradation due to aging and irradiation will subject structures to the possibility of premature failures. In this paper a micro-scale finite element mesh consisting of multiple elements encased in ~50–150μm sized grains with designated grain boundaries is used to replicate shapes and dimensions to simulate an isotropic metallic microstructure. The grains are encased in pseudo-grain boundary element sets which can have different material and damage parameters compared to the grains. In this type of mesh random crack paths for intergranular and transgranular cracking conditions are allowed. It is shown that creep cracking using a uniaxial ductility constraint-based model coupled with a functionally distributed time-dependent environmentally assisted corrosion/oxidation/material degradation damage model acting on surface or internally can be realistically predicted using this model. It is also evident material properties input data have scatter especially at the sub-grain level where the measurement methods are new and not always standardised. This is dealt with in the model by employing a normal distributive probabilistic method to allow for statistically varied random damage and crack growth development. In this way it is possible to take into account the inherent variability in material input properties at the analysis stage without the need to change material properties following each run. The method could negate the need for knowing the exact material properties, which in any case is impossible to derive at the microstructural level, as results of each run can be varied using a statistically distributed critical damage criterion specified for each element.

A simple and general thermodynamic theory is applied to describe the irreversible aspects of the continuous process of functional efficiency loss, which occurs in dissipative biological structures after they reach maturity. Following Prigogine [G. Nicolis and I. Prigogine, Self-organization in Nonequilibrium Systems (Wiley, New York, 1997), pp. 2–3], this theory considers that these dissipative structures perform their functions carrying out cyclic processes per se since they are self-organized far from equilibrium. Starting from the theoretical fact that after biological dissipative systems reach adulthood, the functionality of their organs decreases linearly over time. We show that cumulative damage leads to the exponential law of increasing mortality rate with age for population groups, known as Gompertz’s law. The theory was applied to the determination of functional efficiency loss parameter, $\alpha$, for 71 living beings as a function of mass covering 18 orders of magnitude. The mathematical adjustment allowed us to conclude that there is a minimum in the value of the $\alpha$ parameter for a 23.3 kg mass which is close enough to the Homo sapiens one. We obtained useful expressions to describe the $\alpha$ parameter for smaller masses than those of saccharomyces cerevisiae, so perhaps this theory may contribute to the study of the evolution of some dissipative pre-biological structures.

The accelerated aging test of SBR-based absorption materials in heat seawater were carried in laboratory. The elongation at break of the materials in aging time was investigated. Two methods were adopted to forecast the life expectancy of the materials. Mathematical model was applied through MATLAB software programming to gain the forecasted life expectancy is 10.98y in seawater at 25 ℃. The time-temperature superposition method was applied to gain the life expectancy, which is 12.08y in seawater at 25 ℃.