Effects of four disaccharides on nucleation and growth of ice crystals in concentrated glycerol aqueous solution

Cryobiology ◽  
2019 ◽  
Vol 86 ◽  
pp. 47-51 ◽  
Author(s):  
Mingke Zhang ◽  
Cai Gao ◽  
Bin Ye ◽  
Jingchun Tang ◽  
Bin Jiang
Keyword(s):  
Aqueous Solution ◽  
Nucleation And Growth ◽  
Ice Crystals

Structures Formed by Cryoprotective Agents Used in Freezc-Etching

1971 ◽  
Vol 29 ◽  
pp. 448-449
Author(s):  
G. G. Cocks ◽  
C. E. Cluthe
Keyword(s):  
Aqueous Solution ◽  
Polyethylene Oxide ◽  
Liquid Nitrogen Temperature ◽  
Ice Crystals ◽  
Etching Technique ◽  
Structural Constituent ◽  
Cryoprotective Agents ◽  
Quick Freezing ◽  
Freeze Etching ◽  
Fractured Surface

The freeze etching technique is potentially useful for examining dilute solutions or suspensions of macromolecular materials. Quick freezing of aqueous solutions in Freon or propane at or near liquid nitrogen temperature produces relatively large ice crystals and these crystals may damage the structures to be examined. Cryoprotective agents may reduce damage to the specimem, hut their use often results in the formation of a different set of specimem artifacts.In a study of the structure of polyethylene oxide gels glycerol and sucrose were used as cryoprotective agents. The experiments reported here show some of the structures which can appear when these cryoprotective agents are used.Figure 1 shows a fractured surface of a frozen 25% aqueous solution of sucrose. The branches of dendritic ice crystals surrounded hy ice-sucrose eutectic can be seen. When this fractured surface is etched the ice in the dendrites sublimes giving the type of structure shown in Figure 2. The ice-sucrose eutectic etches much more slowly. It is the smooth continuous structural constituent surrounding the branches of the dendrites.

scholarly journals Синтез гексагональных слоев AlN и GaN на Si(100)-подложке методом хлоридной газофазной эпитаксии

2019 ◽  
Vol 89 (4) ◽  
pp. 574
Author(s):  
В.Н. Бессолов ◽  
Е.В. Гущина ◽  
Е.В. Коненкова ◽  
С.Д. Коненков ◽  
Т.В. Львова ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Buffer Layer ◽  
Vapor Phase ◽  
Silicon Surface ◽  
Nucleation And Growth ◽  
Vapor Phase Epitaxy ◽  
Si Substrate ◽  
Rocking Curve ◽  
Surface Nucleation ◽  
Crystallographic Orientations

AbstractSynthesis of AlN and GaN layers on a Si(100) substrate by chloride vapor-phase epitaxy has been considered. The process includes sulfidizing of the silicon surface, nucleation and growth of an AlN layer, and then formation of a GaN/AlN structure. It has been found that in the case of a (100)Si substrate, GaN nucleates on buffer AlN layers that may have two crystallographic orientations in contrast to a Si(111) substrate, on which a buffer layer may have only one orientation. It has been shown that the treatment of the Si(100) substrate in an aqueous solution of (NH_4)_2S decreases the FWHM of the rocking curve for GaN(0002) by a factor of 1.5.

scholarly journals Nucleation and Growth of Ice Crystals Upon Crystalline Substrates

1960 ◽  
Vol 13 (2) ◽  
pp. 408 ◽  
Author(s):  
NH Fletcher
Keyword(s):  
Free Energy ◽  
Experimental Evidence ◽  
Growth Mechanism ◽  
Energy Barrier ◽  
Nucleation And Growth ◽  
Ice Crystals ◽  
Free Energy Barrier ◽  
Surface Imperfections ◽  
Nucleation Sites ◽  
Entropy Effect

The importance of various surface imperfections in the nucleation of ice crystals iR considered and it is concluded that dislocations are not preferred nucleation sites, whereas steps and re-entrant corners do encourage nucleation. Expressions are derived for the height of the free energy barrier in several important cases, and the retention of embryos under unsaturated conditions is discussed. Embryos initially grow by twodimensional nucleation, but ultimately a dislocation growth mechanism becomes more important. There is not yet enough experimental evidence to decide upon the reality of the entropy effect, previousl:y- proposed, which inhibits nucleation upon certain CITRta] faces.

Rod-Like Rutile Nanoparticles: Synthesis, Structure and Morphology

2017 ◽  
Vol 50 ◽  
pp. 32-40 ◽  
Author(s):  
Volodymyr Kotsyubynsky ◽  
Ivan Myronyuk ◽  
Volodymyr Chelyadyn ◽  
Andrii Hrubiak ◽  
Volodymyr Moklyak ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Hydrochloric Acid ◽  
Specific Surface ◽  
Reaction Medium ◽  
Nucleation And Growth ◽  
Molar Ratio ◽  
Structure And Morphology ◽  
Nanoparticles Synthesis ◽  
Preferred Oriented ◽  
Hydrolysis Of

Nanodispersed rutile with rod-like particles is synthesized by hydrolysis of TiCl4 in hydrochloric acid - ethanol alcohol aqueous solution. It is found that the specific surface area, crystallite size and degree of agglomeration are determined by molar ratio of ethanol in reaction medium. According to HR-TEM images and XRD data rutile crystallites are preferred oriented along the [001] axis. The analysis of the Raman spectra for samples with different morphology is performed. The model of rutile nanorods nucleation and growth is proposed.

Multiscale approach to CO2 hydrate formation in aqueous solution: Phase field theory and molecular dynamics. Nucleation and growth

2006 ◽  
Vol 124 (23) ◽  
pp. 234710 ◽  
Author(s):  
György Tegze ◽  
Tamás Pusztai ◽  
Gyula Tóth ◽  
László Gránásy ◽  
Atle Svandal ◽  
...  
Keyword(s):  
Field Theory ◽  
Molecular Dynamics ◽  
Aqueous Solution ◽  
Phase Field ◽  
Hydrate Formation ◽  
Nucleation And Growth ◽  
Solution Phase ◽  
Multiscale Approach
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