scholarly journals Морфология и структурное состояние частиц нанопорошков, полученных измельчением природного алмаза и методом детонационного синтеза

2020 ◽  
Vol 46 (3) ◽  
pp. 46
Author(s):  
П.П. Шарин ◽  
А.В. Сивцева ◽  
В.И. Попов
Keyword(s):  
High Resolution ◽  
Detonation Synthesis ◽  
Complex Structures ◽  
Interatomic Distances ◽  
Crystal Lattices ◽  
Cubic Crystal ◽  
Noticeable Increase ◽  
Diamond Crystals ◽  
Primary Particles ◽  
Large Diamond

A complex of high-resolution methods has revealed that the nanopowder particles obtained by milling natural diamonds have a wider variety of sizes and predominantly of lamellar shape in contrast to detonation synthesis nanopowder, which consists mainly of similar-sized and isometric particles. The primary particles of the nanopowder obtained by milling, as well as detonation synthesis nanodiamonds, consist of diamond nuclei with cubic crystal lattices surrounded by shells with complex structures, which are formed from carbon atoms in the sp2-state and impurities. A noticeable increase in interatomic distances in nanodispersed diamond crystals has been established compared with those for large diamond crystals.

Confocal fluorescence microscopy with the tandem scanning light microscope

1989 ◽  
Vol 94 (4) ◽  
pp. 617-624
Author(s):  
S.J. Wright ◽  
J.S. Walker ◽  
H. Schatten ◽  
C. Simerly ◽  
J.J. McCarthy ◽  
...  
Keyword(s):  
High Resolution ◽  
Fluorescence Microscopy ◽  
Light Microscope ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Complex Structures ◽  
Charge Coupled Device ◽  
Confocal Fluorescence ◽  
Cooled Ccd ◽  
Cellular Components

Applications of the tandem scanning confocal microscope (TSM) to fluorescence microscopy and its ability to resolve fluorescent biological structures are described. The TSM, in conjunction with a cooled charge-coupled device (cooled CCD) and conventional epifluorescence light source and filter sets, provided high-resolution, confocal data, so that different fluorescent cellular components were distinguished in three dimensions within the same cell. One of the unique features of the TSM is the ability to image fluorochromes excited by ultraviolet light (e.g. Hoechst, DAPI) in addition to fluorescein and rhodamine. Since the illumination is dim, photobleaching is insignificant and prolonged viewing of living specimens is possible. Series of optical sections taken in the Z-axis with the TSM were reproduced as stereo images and three-dimensional reconstructions. These data show that the TSM is potentially a powerful tool in fluorescence microscopy for determining three-dimensional relationships of complex structures within cells labeled with multiple fluorochromes.

HPHT Growth and IR Characterizaton of Large Diamond Crystals in FeNi-C-FeS Systems

2011 ◽  
Vol 339 ◽  
pp. 491-495
Author(s):  
Chuan Yi Zang ◽  
Lun Jian Chen ◽  
Li Xue Chen
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Boron Content ◽  
Diamond Crystals ◽  
Growth System ◽  
Negative Effect ◽  
Temperature Gradient Method ◽  
Co Doped ◽  
Large Diamond

By temperature gradient method (TGM), with Invar alloy as solvent catalyst, FeS and boron as additives, large diamond crystals are grown under high pressure and high temperature (HPHT) of about 5.4GPa and 1550K. With the content of FeS increased, the colors of grown crystals would be changed from transparent yellow to opaque gray-black, and the quality of diamond crystals could also be destroyed markedly. When both boron and FeS co-doped, the negative effect of FeS on crystal quality could be eliminated somewhat. To a certain content of FeS, with the boron content increased, the crystal color would be changed from opaque gray-black to transparent yellow, and boron content needed is related directly to FeS content in growth systems. The nitrogen content in diamond lattice decreases greatly, with FeS content increased in the growth system, and a 1050cm-1 absorption peak in IR spectrum is also present in diamond crystals grown in FeNi-FeS-C system.

scholarly journals Atomic Matching Across Internal Interfaces

1989 ◽  
Vol 153 ◽  
Author(s):  
Karl L. Merkle
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Large Fraction ◽  
High Resolution Electron Microscopy ◽  
Low Energy ◽  
Ideal Lattice ◽  
Interatomic Distances ◽  
Resolution Electron ◽  
Atomic Coordination ◽  
The Ideal

AbstractThe atomic structure of internal interfaces in dense-packed systems has been investigated by high-resolution electron microscopy (HREM). Similarities between the atomic relaxations in heterophase Interfaces and certain largeangle grain boundaries have been observed. In both types of interfaces localization of misfit leads to regions of good atomic matching within the interface separated by misfit dislocation-like defects. It appears that, whenever possible, the GB structures assume configurations in which the atomic coordination is not too much different from the ideal lattice. It is suggested that these kinds of relaxations primarily occur whenever the translational periods along the GB are large or when the interatomic distances are incommensurate. Incorporation of low index planes into the GB appears to lead to preferred, i.e. low energy structures, that can be quite dense with good atomic matching across a large fraction of the interface.

scholarly journals Stem cell-laden hydrogel bioink for generation of high resolution and fidelity engineered tissues with complex geometries

2021 ◽  
Author(s):  
Oju Jeon ◽  
Yu Bin Lee ◽  
Sang Jin Lee ◽  
Nazilya Guliyeva ◽  
Joanna Lee ◽  
...  
Keyword(s):  
Stem Cell ◽  
High Resolution ◽  
Biomedical Applications ◽  
Human Mesenchymal Stem Cells ◽  
Complex Geometries ◽  
Complex Structures ◽  
Self Healing ◽  
3D Bioprinting ◽  
Healing Property

Recently, 3D bioprinting has been explored as a promising technology for biomedical applications with the potential to create complex structures with precise features. Cell encapsulated hydrogels composed of materials such as gelatin, collagen, hyaluronic acid, alginate and polyethylene glycol have been widely used as bioinks for 3D bioprinting. However, since most hydrogel-based bioinks may not allow rapid stabilization immediately after 3D bioprinting, achieving high resolution and fidelity to the intended architecture is a common challenge in 3D bioprinting of hydrogels. In this study, we have utilized shear-thinning and self-healing ionically crosslinked oxidized and methacrylated alginates (OMAs) as a bioink, which can be rapidly gelled by its self-healing property after bioprinting and further stabilized via secondary crosslinking. It was successfully demonstrated that stem cell-laden calcium-crosslinked OMA hydrogels can be bioprinted into complicated 3D tissue structures with both high resolution and fidelity. Additional photocrosslinking enables long-term culture of 3D bioprinted constructs for formation of functional tissue by differentiation of encapsulated human mesenchymal stem cells.

scholarly journals Mapping of complex structures: high resolution 3D renditions of vertical coral reefs

2017 ◽  
Author(s):  
K Robert ◽  
V A I Huvenne ◽  
D O B Jones ◽  
L Marsh ◽  
A Georgiopoulou
Keyword(s):  
High Resolution ◽  
Coral Reefs ◽  
Complex Structures
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