نتایج جستجو برای: nucleation mechanism
تعداد نتایج: 581176 فیلتر نتایج به سال:
Chiral symmetry breaking in stirred crystallization of sodium chlorate (NaCI03) is believed to occur via nucleation of a single chiral "mother crystal" that produces a new generation of crystals which inherit its chirality. We here report results of stirred crystallizations resulting in massive "instantaneous" primary nucleation and total symmetry breaking. The results of these experiments sugg...
The statistics of liquid-to-crystal nucleation are measured rigorously by using a recently developed automated lag-time apparatus (ALTA). A single sample, in this case a sample of pure water both with and without an (insoluble) AgI crystal, is repeatedly cooled, nucleated, and thawed. Analysis of the data, coupled with a second kind of experiment, shows that the statistics of nucleation are con...
Applying a strong static electric field to supersaturated aqueous glycine solutions resulted in the nucleation of the gamma polymorph. This is the first report of a strong dc field inducing the nucleation of a neutral solute in a supersaturated solution. We attribute this effect to the electric-field-induced orientation of the highly polar glycine molecules in large preexisting solute clusters,...
The mechanism of ice nucleation to form Type 2 PSCs is important for controlling the ice particle size and hence the possible dehydration in the polar winter stratosphere. This paper probes heterogeneous ice nucleation on sulfuric acid tetrahydrate (SAT). Laboratory experiments were performed using a thin-film, high-vacuum apparatus in which the condensed phase is monitored via Fourier transfor...
We present a theory of electric field driven phase transitions that occur via nucleation of needle-shaped, metallic particles. The predictions of this theory have much in common with the observations related to nonphotochemical laser induced nucleation (NPLIN). That connection is rather paradoxical because the final NPLIN products are dielectric crystals. By elaborating on the unique features o...
We derive a kinetic Monte Carlo algorithm to simulate flow-induced nucleation in polymer melts. The crystallisation kinetics are modified by both stretching and orientation of the amorphous chains under flow, which is modelled by a recent non-linear tube theory. Rotation of the crystallites under flow is modelled by a simultaneous Brownian dynamics simulation. Our kinetic Monte Carlo approach i...
The mechanism of new particle formation (NPF) events is still poorly understood. The CLOUD experiment is studying at which conditions this process occurs. During the CLOUD 7 campaign (fall 2012) the evolution of the nucleation rate with different reagents (sulphuric acid, ammonia, dimethylamine and -pinene) was tested. Here we investigate the composition of freshly formed positive ions during t...
Ice formation is ubiquitous in nature, with important consequences in a variety of environments, including biological cells, soil, aircraft, transportation infrastructure, and atmospheric clouds. However, its intrinsic kinetics and microscopic mechanism are difficult to discern with current experiments. Molecular simulations of ice nucleation are also challenging, and direct rate calculations h...
In situ microscopy provides dynamic information about nucleation, growth and coalescence of islands in real time. We utilised in situ ultra-high vacuum transmission electron microscopy to gain fundamental insights into the oxidation of Cu films. A semiquantitative model, where oxygen surface diffusion is the dominant mechanism for transport, nucleation and growth of the copper oxide, describes ...
1. Validation of the IMN mechanism against measured atmospheric nucleation rates. The authors argue that the overcharging of the freshly formed nm-sized particles in Hyytiälä indicate IMN whereas Laakso and coworkers have argued that homogeneous nucleation can explain most of the nucleation despite the overcharging. The present authors’ references are not peer-reviewed, and the debate seems ver...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید