The evolution and annealing of pores in, and the crystallization of, vapor-deposited films of amorphous solid water have been studied by using variable-energy positron annihilation spectroscopy for temperatures in the range 50-150 K. Both positron and positronium annihilation provide insight to the nature of the grown-in pores and their evolution with temperature. Crystallization of the films w...

Three types of commercially available ultra-high molecular weight polyethylene (UHMWPE) acetabular cups currently used in total hip arthroplasty have been studied by means of Raman micro-spectroscopy to unfold the microstructural modification induced by the oxidative degradation after accelerated aging with and without lipid absorption. The three investigated materials were produced by three di...

Phase transformations in the supercooled liquid region (between T, and T,,,), prior to the onset of crystallization, in amorphous Pd-Ni-P alloys remain controversial. It has been previously proposed that the amorphous alloy decomposes into two amorphous phases prior to the crystallization reaction when annealed in the supercooled liquid region. Investigations by DSC, Mossbauer spectroscopy, X-r...

Lithium-ion batteries have revolutionized portable electronics and will be a key to electrifying transport vehicles and delivering renewable electricity. Amorphous silicon (a-Si) is being intensively studied as a high-capacity anode material for next-generation lithium-ion batteries. Its lithiation has been widely thought to occur through a single-phase mechanism with gentle Li profiles, thus o...

The amorphous, liquid and crystalline phases of the phase change material Ge(2)Sb(2)Te(5) (GST) have been studied by means of density functional/molecular dynamics simulations. The large sample (460 atoms and 52 vacancies in the unit cell) and long simulations (hundreds of picoseconds) provide much new information. Here we extend our original analysis (2007 Phys. Rev. B 76 235201) in important ...

Ga:La:S:Cu films have been prepared by sputter deposition. Amorphous thin films were fabricated with Cu concentrations as high as 66 at.%. The electrical phase change properties of these films have been investigated. The electrical resistivity of these materials is 200 Om in the amorphous state and 40 Om in the crystalline state. The crystallisation time was measured using an optical pump probe...

Poly(ethylene terephthalate) (PET) is a semi–crystalline polymer that can be crystallized to different degrees heating from the amorphous state. Even when primary crystallization has been completed, secondary crystallization can take place with further annealing and modify the characteristics of the amorphous interlamellar phase. In this work we study the glass transition of highly crystallized...

Amorphous and crystalline powder of PLT phase was synthesized by using the Pechini method. Infrared (FTIR) analysis of the polymeric resin shows intense bands of organic materials from 250 to 1620 cm−1. X-ray diffraction (XRD) and Raman spectra of calcined powder at different temperatures show amorphous phase at 450 ◦C/3 h, semi-crystalline phase at 550 ◦C/3 h and a crystalline phase at 800 ◦C/...

Phase-change materials are functionally important materials that can be thermally interconverted between metallic (crystalline) and semiconducting (amorphous) phases on a very short time scale. Although the interconversion appears to involve a change in local atomic coordination numbers, the electronic basis for this process is still unclear. Here, we demonstrate that in a nearly vacancy-free b...

Amorphous computing considers the problem of controlling millions of spatially distributed unreliable devices which communicate only with nearby neighbors. To program such a system, we need a highlevel description language for desired global behaviors, and a system to compile such descriptions into locally executing code which robustly creates and maintains the desired global behavior. I survey...