Crystallization of α – Fe phase during annealing process of Fe55Cr18Mo7B16C4 bulk amorphous alloy has been evaluated by X- ray diffraction, differential scanning calorimetric tests and TEM observations in this research. In effect, crystallization mechanism and activation energy of crystallization were evaluated using DSC tests in four different heating rates (10, 20, 30, 40 K/min). A two -st...

The temperature dependence of the crystallite nucleation and growth rates is measured for amorphous NiTi thin films. Using transmission electron microscopy, crystallites are shown to nucleate homogeneously in the film and to grow in a channeling mode. A mechanism that suppresses heterogeneous nucleation is proposed. By manipulating nucleation and growth rates, grains as large as 60 lm can be ob...

We analyse a new mechanism for the cosmological QCD first-order phase transition: inhomogeneous nucleation. The primordial temperature fluctuations are larger than the tiny temperature interval, in which bubbles would form in the standard picture of homogeneous nucleation. Thus the bubbles nucleate at cold spots. We find the typical distance between bubble centers to be a few meters. This excee...

To investigate the mechanisms by which oligonucleotides hybridize to target molecules, the binding of two oligodeoxynucleotide probes to RNA targets was measured over a broad range of temperatures. Mutations were then scanned across each DNA/RNA hybrid to map, at single base resolution, sequences important for hybridization. Despite being unrelated in sequence, each hybrid formed by a similar m...

We explore the free energetics of bubble nucleation in the micellar solution subjected to a negative pressure using a density functional model of a non-ionic surfactant solution. In this two-component model, the solvent is represented by a single hard-core sphere and the surfactant is represented by two tangent hard-core spheres connected by a rigid bond. The attractive interactions between the...

A new experimental method, called the 'hole filling method', is proposed to simulate the healing of internal cracks in rolled workpieces. Based on the experimental results, the evolution in the microstructure, in terms of diffusion, nucleation and recrystallisation were used to analyze the crack healing mechanism. We also validated the phenomenon of segmented healing. Internal crack healing inv...

A comprehensive crystallization kinetics study was carried out in order to understand the mechanism of formation of a Mg-rich nanocrystalline Mg6Ni phase in a metallic glass with similar overall composition, Mg83Ni17. Adequate description of the transformation kinetics was obtained by the JMKA equation with an integer Avrami exponent n = 4, associated with nucleation and three-dimensional linea...

The mechanism of ice nucleation at the molecular level remains largely unknown. Nature endows antifreeze proteins (AFPs) with the unique capability of controlling ice formation. However, the effect of AFPs on ice nucleation has been under debate. Here we report the observation of both depression and promotion effects of AFPs on ice nucleation via selectively binding the ice-binding face (IBF) a...

The central control of mineral weathering rates on biogeochemical systems has motivated studies of dissolution for more than 50 years. A complete physical picture that explains widely observed variations in dissolution behavior is lacking, and some data show apparent serious inconsistencies that cannot be explained by the largely empirical kinetic "laws." Here, we show that mineral dissolution ...