Interface-Kinetics-Driven Facet Formation during Melt Growth of Oxide Crystals

Magnetosomes are membrane-enclosed iron oxide crystals biosynthesized by magnetotactic bacteria. As the biomineralization of bacterial magnetosomes can be genetically controlled, they have become promising nanomaterials for bionanotechnological applications. In the present paper, we explore a novel application of magnetosomes as nanotool for manipulating axonal outgrowth via stretch-growth (SG). SG refers to the process of stimulation of axonal outgrowth through the application of mechanical forces. Thanks to their superior magnetic properties, magnetosomes have been used to magnetize mouse hippocampal neurons in order to stretch axons under the application of magnetic fields. We found that magnetosomes are avidly internalized by cells. They adhere to the cell membrane, are quickly internalized, and slowly degrade after a few days from the internalization process. Our data show that bacterial magnetosomes are more efficient than synthetic iron oxide nanoparticles in stimulating axonal outgrowth via SG.

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Recent progress in production of infiltration-growth and melt-growth processed bulk (RE)Ba2Cu3Oy

Superconductor Science and Technology ◽

10.1088/1361-6668/ab877a ◽

2020 ◽

Vol 33 (7) ◽

pp. 074002

Author(s):

M Muralidhar ◽

P Sunsanee ◽

K Takemura ◽

A Sai Srikanth ◽

M Jirsa ◽

...

Keyword(s):

Recent Progress ◽

Melt Growth ◽

Infiltration Growth

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Ge-Quantum Dots on SI(001) Tailored by Carbon Predeposition

MRS Proceedings ◽

10.1557/proc-533-183 ◽

1998 ◽

Vol 533 ◽

Cited By ~ 7

Author(s):

O. Leifeld ◽

D. Grützmacher ◽

B. Müller ◽

K. Kern

Keyword(s):

Surface Roughness ◽

Critical Thickness ◽

Carbon Deposition ◽

Compressive Strain ◽

Second Step ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Island Nucleation ◽

Facet Formation

AbstractThe morphology of Si(001) after carbon deposition of 0.05 to 0.11 monolayers (ML) was investigated in situ by ultrahigh vacuum scanning tunneling microscopy (UHV-STM). The carbon induces a c(4×4)-reconstruction of the surface. In addition, carbon increases the surface roughness compared to clean Si(001) (2×1). In a second step, the influence of the carbon induced restructuring on Ge-island nucleation was investigated. The 3D-growth sets in at considerably lower Ge coverage compared to the clean Si(001) (2×1) surface. This leads to a high density of small though irregularly shaped dots, consisting of stepped terraces, already at 2.5 ML Ge. Increasing the Ge-coverage beyond the critical thickness for facet formation, the dots show { 105 }- facets well known from Ge-clusters on bare Si(001) (2×1). However, they are flat on top with a (001)-facet showing the typical buckled Ge rows and missing dimers. This indicates that the compressive strain is not fully relaxed in these hut clusters.

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