Particle nucleation and growth mechanisms in miniemulsion polymerization of styrene

2002 ◽  
Vol 51 (12) ◽  
pp. 1428-1438 ◽  
Author(s):  
Chorng-Shyan Chern ◽  
Hung-Te Chang
Keyword(s):  
Miniemulsion Polymerization ◽  
Nucleation And Growth ◽  
Particle Nucleation ◽  
Growth Mechanisms ◽  
Nucleation And Growth Mechanisms

Crystal structure images of large gold clusters and growing crystals by HRTEM

1984 ◽  
Vol 42 ◽  
pp. 428-429
Author(s):  
L.R. Wallenberg ◽  
J.-O. Bovin ◽  
G. Schmid
Keyword(s):  
Crystal Structure ◽  
Nucleation And Growth ◽  
Close Packing ◽  
Gold Clusters ◽  
Molecular Weight Determination ◽  
Growth Mechanisms ◽  
Starting Point ◽  
Different Types ◽  
Nucleation And Growth Mechanisms ◽  
Points Of View

Metallic clusters are interesting from various points of view, e.g. as a mean of spreading expensive catalysts on a support, or following heterogeneous and homogeneous catalytic events. It is also possible to study nucleation and growth mechanisms for crystals with the cluster as known starting point.Gold-clusters containing 55 atoms were manufactured by reducing (C6H5)3PAuCl with B2H6 in benzene. The chemical composition was found to be Au9.2[P(C6H5)3]2Cl. Molecular-weight determination by means of an ultracentrifuge gave the formula Au55[P(C6H5)3]Cl6 A model was proposed from Mössbauer spectra by Schmid et al. with cubic close-packing of the 55 gold atoms in a cubeoctahedron as shown in Fig 1. The cluster is almost completely isolated from the surroundings by the twelve triphenylphosphane groups situated in each corner, and the chlorine atoms on the centre of the 3x3 square surfaces. This gives four groups of gold atoms, depending on the different types of surrounding.

A TEM study of the microstructure of avian eggshells

1992 ◽  
Vol 50 (2) ◽  
pp. 1102-1103
Author(s):  
S. Q. Xiao ◽  
S. Baden ◽  
A. H. Heuer
Keyword(s):  
Electron Microscope ◽  
Calcium Carbonate ◽  
Nucleation And Growth ◽  
Growth Mechanisms ◽  
Shell Surface ◽  
Thin Sections ◽  
Polycrystalline Metals ◽  
Transmission Electron ◽  
Nucleation And Growth Mechanisms

The avian eggshell is one of the most rapidly mineralizing biological systems known. In situ, 5g of calcium carbonate are crystallized in less than 20 hrs to fabricate the shell. Although there have been much work about the formation of eggshells, controversy about the nucleation and growth mechanisms of the calcite crystals, and their texture in the eggshell, still remain unclear. In this report the microstructure and microchemistry of avian eggshells have been analyzed using transmission electron microscope (TEM) and energy dispersive spectroscopy (EDS).Fresh white and dry brown eggshells were broken and fixed in Karnosky's fixative (kaltitanden) for 2 hrs, then rinsed in distilled H2O. Small speckles of the eggshells were embedded in Spurr medium and thin sections were made ultramicrotome.The crystalline part of eggshells are composed of many small plate-like calcite grains, whose plate normals are approximately parallel to the shell surface. The sizes of the grains are about 0.3×0.3×1 μm3 (Fig.l). These grains are not as closely packed as man-made polycrystalline metals and ceramics, and small gaps between adjacent grains are visible indicating the absence of conventional grain boundaries.

Nucleation and growth mechanisms of interfacial carbide in graphene nanosheet/Al composites

Carbon ◽  
2020 ◽  
Vol 161 ◽  
pp. 17-24 ◽  
Author(s):  
Yuanyuan Jiang ◽  
Zhanqiu Tan ◽  
Genlian Fan ◽  
Zhibo Zhang ◽  
Ding-Bang Xiong ◽  
...  
Keyword(s):  
Nucleation And Growth ◽  
Growth Mechanisms ◽  
Graphene Nanosheet ◽  
Nucleation And Growth Mechanisms

Nucleation and Growth Mechanisms in Cu–Co Films

2016 ◽  
Vol 120 (39) ◽  
pp. 22142-22154 ◽  
Author(s):  
M. del C. Aguirre ◽  
H. Núñez Coavas ◽  
L. M. Fabietti ◽  
S. E. Urreta
Keyword(s):  
Nucleation And Growth ◽  
Growth Mechanisms ◽  
Nucleation And Growth Mechanisms
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