We have performed experimental measurements and computer simulations of the equilibrium structure and folding of a 21-residue alpha-helical heteropeptide. Far ultraviolet circular dichroism spectroscopy is used to identify the presence of helical structure and to measure the thermal unfolding curve. The observed melting temperature is 296 K, with a folding enthalpy of -11.6 kcal/mol and entropy...

In solid-liquid systems, macroscopic solids lose their equilibrium and melt in a manner that results in overall movement of the solid-liquid interface. This phenomenon occurs when they are subjected to temperature gradients or external stress, for example. However, many experiments suggest that the melting of nano- and micro-sized metallic nuclei follows a different process not described by tra...

We discuss the microscopic mechanisms by which low-temperature amorphous states, such as ultrastable glasses, transform into equilibrium fluids, after a sudden temperature increase. Experiments suggest that this process is similar to the melting of crystals, thus differing from the behaviour found in ordinary glasses. We rationalize these observations using the physical idea that the transforma...

Walter Kauzmann's classic 1948 review of liquid supercooling and glass formation drew attention to the temperatures at which (by extrapolation) enthalpies and entropies of liquid and crystal phases would appear to become equal. In the temperature-pressure (T, p) plane, the collection of such 'Kauzmann temperatures' generate characteristic curves. The present study examines the connection of tho...

The density and the specific heat of liquid Au–Cu alloy above and below the melting temperature are investigated in a wide composition range via constant temperature and constant pressure molecular dynamics simulations. The atomic interaction of the alloy is described with the embedded-atom method (EAM). The equilibrium melting temperature is evaluated from the change in the growth direction of...

The melting curve and fluid equation of state of carbon dioxide have been determined under high pressure in a resistively heated diamond anvil cell. The melting line was determined from room temperature up to 11.1+/-0.1 GPa and 800+/-5 K by visual observation of the solid-fluid equilibrium and in situ measurements of pressure and temperature. Raman spectroscopy was used to identify the solid ph...

We have performed large-scale molecular dynamics simulations of coexisting solid and liquid phases using 4e(s/r) interactions for n59 and n512, and for Lennard-Jones systems, in order to calculate the equilibrium melting curve. The coexisting systems evolve rapidly toward the melting temperature. The P – T melting curves agree well with previous calculations, as do the other bulk phase properti...

agar is a gelling biopolymer that can be extracted from cell wall of some red algae. in this present, response surface methodology was used to investigate the procedure of agar melting point and gelling temperature from cultural algae of gracilariopsis persica. independent variables, alkalinity concentration (2, 3.2, 5, 6.8, -8%), extraction temperature (90, 96, 105, 114, 120°c) and extraction ...