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To get accurate aging mechanical properties of aged HTPB propellant, the thermal accelerated aging experiment method is utilized and the uniaxial tensile experiments were conducted to obtain the mechanical data of aged HTPB propellants, and the maximum tensile strength, σm, maximum tensile strain, em, and the fracture tensile strain, eb, of HTPB propellant with different aging time and various aging temperatures,were obtained, using universal material testing machine. The experimental results show that the σm of HTPB propellant initially increases, subsequently decreases and finally increases with aging time. The em and eb generally decrease with increasing aging time, what’s more, the decrease rate of both em and eb reduce with the aging time. What’s more, the postcure effect and oxidation reaction occurred inside HTPB matrix, including the chain degradation reaction and oxidation-induced crosslinking, were discussed to explain the mechanical aging rule of HTPB propellant.

The paper presents research results on the temperature dependence of inelastic strain recovery due to superelasticity and shape memory effects under torsion in coarse-grained and microcrystalline TiNi specimens containing 50.8 at % of Ni (Ti49.2Ni50.8 (at %)). It is found that under certain temperature and deformation conditions, the recovery strain exceeds the theoretical limit of recoverable strains or maximum lattice strain in B2↔R↔B19′ transformations. Using a special algorithm, the torsional strain is converted to its equivalent (by Mises) tensile strain. The results are compared with data obtained by other researchers.

We have performed a comparative study of total three films, two films of NdNiO3 deposited on SrTiO3 (STO) and NdGaO3 (NGO) single-crystals and one 10% Mn-doped thin film of NdNi0.9Mn0.1O3 deposited on NGO. We find that both, the enhanced tensile strain and the Mn-doping drive the system to an insulating state from a metallic state at high temperatures. NdNiO3/NGO film shows a metal-insulator transition, which disappears in the other two films due to opening of charge-transfer gap. These results reveal that the effect of tensile strain on the resistivity of NdNiO3 is profound at low temperatures, whereas Mn-doping clearly dominates at high temperatures.

We have studied the effects of Mn-doping in a series of NdNi1−xMnxO3 (x = 0, 0.10) thin films deposited on NdGaO3 (001) and YAlO3 (100) substrates, respectively with tensile and compressive in-plane strains. Interestingly, only 10% Mn-doping totally suppresses the metallicity in both the thin films indicating an opening of charge-transfer gap. In addition, we have also observed contrasting effects of compressive and tensile strains on electrical transport of Mn-doped thin films. There is an enhancement in magnetization as a result of Mn-doping.

In this paper, the strain effect on saturation optical intensity in electroabsorption modulators (EAMs) based on asymmetric intra‐step‐barrier coupled double strained quantum well (AICD‐SQWs) active region is theoretically investigated and compared with intra‐step quantum well (IQW) structure. For this purpose, the thermionic emission and tunneling escape processes are taken into account and the escape times of photogenerated carriers are calculated. Then, the electroabsorption coefficient is calculated for different well strains for TE input light polarization. Finally, the saturation optical intensity of electroabsorption modulators with AICD‐SQW structures in comparison with IQW structure is evaluated. Numerical results show that the tensile strain of well has the most significant effect on the saturation optical intensity of electroabsorption modulators with AICD‐SQW structures due to reduction in escape times.

Due to the tensile strain in the GaN0.02As0.98 layer, photoreflectance features related to light hole (LH) and heavy hole (HH) transitions are well separated (∼31 meV) and can be precisely analyzed. A careful analysis of the experimental data has shown that at low temperatures both the LH and the HH transitions are composed of two resonances. The first is related to excitonic absorption and the second related to band‐to‐band absorption. The exciton binding energies, determined from the splitting of the two contributions, are ∼4.7 meV and ∼6.2 meV for LH and HH excitons, respectively.