In this paper, we present a first-principles and molecular dynamics study to delineate the functionalization-induced changes in the local structure and the physical properties of amorphous polyaniline. The results of radial distribution function (RDF) demonstrate that introducing -SO3−Na+ groups at phenyl rings leads to the structural changes in both the intrachain and interchain ordering of polyaniline at shorter distances (≤5 Å). An unique RDF feature in 1.8–2.1 Å regions is usually observed in both the interchain and intrachain RDF profiles of the -SO3−Na+ substituted polymer (i.e. Na-SPANI). Comparative studies of the atom-atom pairs, bond structures, torsion angles and three-dimensional structures show that EB-PANI has much better intrachain ordering than that of Na-SPANI. In addition, investigation of the band gap, density of states (DOS), and absorption spectra indicates that the derivatization at ring do not substantially alter the inherent electronic properties but greatly change the optical properties of polyaniline. Furthermore, the computed diffusion coefficient of water in Na-SPANI is smaller than that of EB-PANI. On the other hand, the Na-SPANI shows a larger density than that of EB-PANI. The computed RDF profiles, band gaps, absorption spectra, and diffusion coefficients are in quantitative agreement with the experimental data.

10-meter-long Ag-Ni bimetallic sheathed (Bi,Pb)-2223 tapes with outer nickel sheath and inner silver sheath have been successfully fabricated by the "Powder in tube" technique. Microstructure and phase evolution studies by means of SEM and XRD, as well as critical current density (J c ) measurements have been performed. It is found that the nickel sheath and dwell time in the first sintering process have great influences on the texture evolution, phase transformation and J c of the Bi-2223/Ag/Ni tapes. Monofilament (Bi,Pb)-2223 tape with a J c of 6656 A cm −2 and 61-filament tape with a J c of 12420 A cm −2 are obtained. Although using composite bimetallic sheaths can reduce production costs and improve mechanical properties of the Bi-2223 tapes, the Bi-2223 content and J c of Bi-2223/Ag/Ni tapes are relatively lower than that of traditional Bi-2223/Ag tapes. Meanwhile, due to higher Bi-2223 content and better alignment of Bi-2223 grains, tapes with 61-filament have higher J c than mono-filament tapes.

The effects of a homogenisation treatment on precipitation, recrystallisation, grain refinement and texture in an Al–1.2Mn alloy were investigated. Based on hardness and electrical conductivity measurements, a precipitation–recrystallisation diagram was generated, which described the sequence of recrystallisation and precipitation. The results showed that recrystallisation was significantly retarded during the annealing treatment for the cold-rolled alloys with a supersaturated solid solution or with dense pre-existing dispersoids. If precipitation occurred prior to recrystallisation, the precipitates caused a strong resistance to recrystallisation, resulting in a coarse and elongated grain structure with a dominant normal direction-rotated cube texture. In contrast, when recrystallisation was completed before precipitation, recrystallisation was little affected by the precipitates, leading to a fine-grained structure with a weak cube texture.

Bi‐2223 ceramic grain growth in Ag/Ni composite‐sheathed tapes sintered at different oxygen partial pressures was investigated systematically. The effect of oxygen partial pressure on the evolution of phases, texture, and microstructure development in tapes was characterized by X‐ray diffraction and scanning electron microscope. Development curves of Bi‐2223 phase at different oxygen partial pressures were different, indicating that they were in different formation stages of Bi‐2223 during the sintering period. The appearance time of optimized texture in Bi‐2223/Ag/Ni tapes was influenced greatly by oxygen partial pressure, which had an essential effect on Bi‐2223 formation and growth. Grain size in nonfully reacted tapes sintered at higher oxygen partial pressure was smaller than that in tapes sintered at lower oxygen partial pressure, which was opposite to the result in fully reacted tapes. Depending on the above results, growth process of Bi‐2223 platelets at different oxygen partial pressures was expounded in detail combined with kinetics.