نتایج جستجو برای: nucleation density
تعداد نتایج: 426783 فیلتر نتایج به سال:
A nonperturbative correction to the thermal nucleation rate of critical bubbles in a first-order phase transition is estimated. Using a simple model of a scalar field in a double-well potential, we obtain a corrected potential which incorporates the free-energy density available from large-amplitude fluctuations, which is not included in the usual perturbative calculation. As an application of ...
Constant temperature and pressure molecular-dynamics simulations in conjunction with constant pressure and enthalpy simulations, designed to examine the threshold behavior in laser ablation, demonstrate that the rate of homogeneous nucleation (explosive boiling) increases sharply in a very narrow temperature range at approximately 90% of the critical temperature. Moreover, the homogeneous nucle...
Density functional theory is applied to ion-induced nucleation of polarizable multipolar molecules. The asymmetric nature of the ion–molecule interaction is shown to cause the sign preference in ion-induced nucleation. When the ion–molecule interaction is weak, the observed sign preference is consistent with that of the bare ion–molecule interaction potential and decreases with increasing super...
A general theory of nucleation for colloids and macromolecules in solution is formulated within the context of fluctuating hydrodynamics. A formalism for the determination of nucleation pathways is developed and stochastic differential equations for the evolution of order parameters are given. The conditions under which the elements of classical nucleation theory are recovered are determined. T...
The effects of adsorbates on nucleation and growth of twodimensional islands is investigated by kinetic Monte Carlo simulations and rate equation theory. The variation of island morphology with adsorbate parameters is discussed and the temperature-dependence of island density in the case of immobile adsorbates is studied in detail. A set of rate equations for the description of nucleation in th...
In this paper, we systematically studied the effects of coronene as nucleation seeds for graphene synthesis at low temperatures by chemical vapor deposition. Naphthalene was used as a solid carbon source which is capable of producing graphene at temperatures down to 300 °C. The experimental results showed clear evidence that coronene seeds work as preferred nucleation sites, through which the n...
The nucleation path of graphene growth on the Cu(111) surface is investigated by importing carbon atoms step-by-step using density functional theory (DFT) calculations. An overall path of graphene nucleation has been proposed based on configuration and energy analysis. At the very first stage, linear chains will be formed and dominate the copper surface. Then, Y-type (furcate) carbon species wi...
Few physical processes are as ubiquitous as the nucleation of water into ice. However, ice nucleation and, in particular, heterogeneously catalyzed nucleation remains poorly understood at the atomic level. Here, we report an initial series of density functional theory (DFT) calculations aimed at putting our understanding of ice nucleation and water clustering at metallic surfaces on a firmer fo...
On electropolished steel at low current densities, morphology and texture of electrodeposited zinc were investigated. Zinc coating is consisted of hexagonal crystallites laid on each other to produce packets. These packets are of different sizes and are stacked in different orientations to construct a homogeneous coating on steel substrate. This coating does not have texture, i.e., it has a ran...
Zinc was electrodeposited from an acidic sulphate solution on commercial steel sheet substrates galvanostatically at 10, 20, and 100 mA/cm2. The steel substrates had an average roughness number of 1.34 microns and a high percentage of its grains had their (111) planes parallel to the plate surface. During electrodeposition at 10 mA/cm2, on some specimens, there was an intense potential fluctuat...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید