The configurations of terminating bands in Er isotopes are investigated using the unpaired cranked Nilsson-Strutinsky (CNS), and the paired cranked Nilsson-Strutinsky-Bogoliubov (CNSB) models and also, new CNS(B) formalism. The calculated excitation energies of the bands have been compared with the experimental findings, and good agreements are observed. Our calculations show that the CNS(B) approach successfully is in agreement CNSB predictions and experimental results. Some systematics of terminating bands in erbium isotopes are also discussed.

Essential understanding about the structure of rotating nuclei has come from the study on the band crossings which are often associated with the alignment of a pair of quasiparticles. In this work, the first and second discontinuities in the low-lying rotational bands of [Formula: see text]Er nuclei have been investigated systematically, for the first time, within the paired cranked Nilsson–Strutinsky–Bogoliubov (CNSB) framework. Our calculations show these irregularities are related to the high-j intruder [Formula: see text] neutron and [Formula: see text] proton alignment, which is consistent with the previous studies within the cranked shell model (CSM) approach. A comparison was made with the experimental data where available, and good agreement is observed.

In a terminating band, the nucleon number changes in a specific orbital not only lead to deformation changes of the band but also the type of the band termination is impressed. In this work, we consider the role of the orbitals near the Fermi surface in some of the nuclei with [Formula: see text]; such as Dy ([Formula: see text]), Ho ([Formula: see text]) and Er ([Formula: see text]) isotopes. Our results show that the contribution of the number of the proton holes in the core is very effective to energy cost at the end of the rotational bands and then, termination type. Change the number of the protons on high-[Formula: see text] orbitals ([Formula: see text]) in [Formula: see text] isotones and also, the neutrons on high-[Formula: see text] [Formula: see text] and low-[Formula: see text] [Formula: see text] neutron orbitals do not affect in the type of termination. They cause only to move up or down the terminating bands in energy.

Band termination in different mass regions exhibits some similar characteristics. High spin states in odd-A 107−113Sb (Z = 51) and 155−157Ho (Z = 67) isotopes in addition to the N = 58 and N = 88 isotones are investigated within the cranked Nilsson-Strutinsky (CNS) approach. Also, experimental and calculation results are compared with a focus on the number of the holes and particles in different orbitals. Consequently, we deduce similarities and differences in the structure of the terminating bands in A ∼ 110 and the A ∼ 160 mass regions.

In the present work, we investigate the general properties of low-lying experimental bands in three isotones, 155Dy , 156Ho , 157Er , at high spin within the cranked Nilsson-Strutinsky formalism. The excitation energies of the yrast bands have been compared with the experimental findings, and good agreements are observed. Our calculations show that with increasing total nuclear spin, the collectivity decreases gradually leading to the termination. In addition, nuclei with 10–12 particles outside the closed core terminate within configurations with no hole in the core.

A new type of Fe-based metallic glass (FMG) and SiC reinforced hybrid composite was successfully developed. The current work was set to evaluate the microstructure and mechanical properties of the hybrid composite consolidated through the spark plasma sintering (SPS) process. The densities of the samples were determined in order to examine the performance of the sintering process. The experimental results indicated that, in the composites having larger amounts of FMG particles, the reinforcements/matrix interfaces were free from any discontinuities. The quantitative analysis of microstructural features revealed that the more homogenous distribution of reinforcing particles was occurred for FMG rich composites. The microstructural analysis of the samples pointed that the amorphous structure of the FMG reinforcement remained unchanged and no interfacial chemical products were created in the consolidated samples. It was also found that using FMG along with SiC particles in the samples led to the more strengthening of the Al matrix compared to using just one type of reinforcement particles. In the current study, the hybrid composite reinforced with 7 vol% of FMG and 3 vol% of SiC particles demonstrated the optimum combination of compressive yield strength (98 MPa) and strain to fracture (62.8%). The strengthening mechanisms in all the consolidated samples were calculated quantitatively considering the load bearing of reinforcing particles, grain boundary and strain hardening mechanisms. The strain hardening with the contribution of about 30% in the yield strength was the predominant strengthening mechanism in the composite samples. Also, there was a reasonable agreement between the calculated and experimentally obtained yield strength for hybrid composite samples.

In this study, Al matrix hybrid composites reinforced with amorphous/ceramic particles have been produced via powder metallurgy process. Pure aluminum powder particles were blended with various volume fractions of TiH2 and amorphous Fe75Si15B5Zr5 particles. Blended powders were then consolidated through spark plasma sintering (SPS). The microstructure, phase evolution and mechanical properties of composites were examined. Microstructural investigations indicated that the reinforcing particles were segregated along the grain boundaries and mean grain sizes were decreased by increasing the amorphous particles content. Also, increasing the volume fraction of reinforcements had negligible effect on the porosity content of composites. Phase investigations revealed the presence of amorphous phase in the XRD patterns and absence of any undesirable matrix/reinforcement interfacial products. Compared to composite without amorphous reinforcements, the yield strength and hardness of composites contain 15 vol. % of amorphous particles and 1 vol. % of TiH2 particles were enhanced for 35% and 20%, respectively.

The structure, electronic band structure, density of state, projected wave function, and optical properties of mullite-type orthorhombic Bi2M4O9 (M = Al(3+), Ga(3+)) crystals have been studied by applying density functional theory based on the Vanderbilt ultrasoft pseudopotential in the frame of the generalized gradient approximation as an exchange-correlation function. Satisfactory agreement between experimental and theoretical results indicates that the used method and conditions are suitable. M-O bonds in tetrahedral MO4 environments are stronger and more covalent with respect to octahedral MO6; also Bi-O bonds in both studied structures are almost ionic in nature. The photocatalytic activity of Bi2Al4O9 and Bi2Ga4O9 is enhanced due to unequal values of Mulliken charges on the O atoms in MO4, MO6, and BiO6E groups. Bi2Al4O9 and Bi2Ga4O9 are direct and indirect band gap semiconductors with band gaps of 2.71 and 2.86 eV, respectively. Higher photocatalytic activity of Bi2Al4O9 is inferable from the lower effective masses of photogenerated carriers around the conduction band minimum and valence band maximum, in comparison with Bi2Ga4O9. The presence of M and O orbitals in the valence and conduction bands reveals that symmetry breaking in the MO4 and MO6 units has an important role in separating charges and increasing photocatalytic activity. Photocatalytic activities of Bi2Al4O9 and Bi2Ga4O9 for decomposition of organic pollutants and generation of hydrogen from water splitting are confirmed from band edge potentials.