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Size-dependent freezing temperature of metallic and semi-metallic nanoparticles

“…It can be assumed that r* of bulk and nanomaterials is the same value [5] for the first approximation and combining it with Eqs.…”

“…For nanomaterials, there exists a hysteresis between T m (r) and T f (r). The hysteresis decreases with the size decrease and it will disappear at the critical size [2,[4][5][6][7][8]. Aguado et al [9] indicated that what size the liquid and solid phases of a nanoparticle start to coexist in contact is an interesting and important questions that remain to be addressed.…”

“…All the results indicate the fact that the T f (r) depresses with the decreasing size and two temperatures (T f (r) and T m (r)) will meet at the critical size. In order to make clear the change of T f (r) with size and obtain the exact value of critical radius to provide guidance for experiments and applications, many theoretical attempts have been made, such as Zhang's thermodynamics model [5], from which the changing tendency of T f (r) can be well estimated. However, it ignores the temperature-effect on solidliquid interface energy g sl (r,T) and in fact, when the temperature is higher than Kauzmann temperature T k , g sl (r,T) is a measure of the temperature effect [12].…”

Research on Polymerization Processes of Cationic Polyacrylate Emulsion and its Optimization

“…These are many factors which affect the properties of cationic polyacrylate emulsion such as drop time, reaction temperature and reaction time and so on. It is very impotent to study the effect of these factors on the emulsion properties [3][4]. Cationic polyacrylate emulsion was prepared in lab by semi-continuous seed pre-emulsification process, the orthogonal experiments after the single factor experiments were made to get the optimal polymerization processes, and get a satisfactory result.…”

Modelling of the melting temperature of nano-ice in MCM-41 pores

“…However, the results from the two methods (that of [3,6] and that of [8]) correspond well (within the measurement error range) to the model prediction: T m (r) diminishes with decrease in scale although the lowest measured T m (r) of 193 K is a little higher than the prediction of 185 K. Theoretically, T f (∞) < T m (∞), due to the non-equilibrium process of nucleation during the freezing. However, when r = 1 to 5 nm, the nucleation barrier or Gibbs free energy of melting approaches zero [9] and thus T f (r) ≈ T m (r) in experiments [18]. Inserting numerical values of r 0 and α into equation ( 12) (as regards the details of the calculations, see the figure caption), C = 0.215 nm and t = 0.552 nm, while the experimental fitting parameters are C = 0.19 nm and t = 0.59 nm, respectively [6]; these are in quite surprisingly agreement with our model predictions, considering the assumptions and limitations of the model.…”