Pore growth kinetics in heat-treated glass-like carbons

The kinetics of changes in void size during annealing of glass-like carbons in the temperature range 1000°−2800 °C for times up to 150 h were studied using small-angle x-ray scattering determinations of the radius of gyration Rg. The results show that Rg ranged from 9 Å at 1000°C to about 24 Å at 2800 °C. A pore coarsening analysis and a superimposition kinetic analysis applied to Rg gave activation energies of 76 ± 4 kcal/mole and 74 ± 9 kcal/mole, respectively, which are associated with migration of vacancies within graphitic layers in the matrix material.

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Employing X-ray scattering to characterize materials with grain sizes in the nano-regime

Powder Diffraction ◽

10.1154/1.2912231 ◽

2008 ◽

Vol 23 (2) ◽

pp. 96-100 ◽

Cited By ~ 1

Author(s):

E. A. Laitila ◽

D. E. Mikkola

Keyword(s):

Crystallite Size ◽

Large Fraction ◽

Matrix Material ◽

Background Intensity ◽

X Ray ◽

Volume Fractions ◽

X Ray Scattering ◽

The Matrix ◽

Diffraction Peaks ◽

Ray Scattering

This study focuses on characterization of an (Al,Cr)3Ti alloy processed together with titanium powder by reactive mechanical milling (RMM) to produce an ultrafine grained intermetallic alloy matrix with in situ carbide and hydride phases formed during processing. Observations of X-ray scattering as RMM processing time increases show severe broadening of matrix diffraction peaks, accompanied by the appearance of diffraction peaks resulting from the formation of very small crystallites of TiC and TiH1.92 phases with increasing volume fractions, and finally, increasing background intensity as the crystallite size of the matrix phase decreases to ∼2 nm. Estimates of phase volume fractions were made by the direct comparison method, along with crystallite sizes by Warren–Averbach peak profile analysis. The general increase in background intensities has been attributed to random static displacements of the large fraction of atoms located within the grain boundary regions. Further, it has been concluded that the matrix material with a crystallite size of a few nanometers has about half the atoms in statically displaced positions defining the boundary regions. The results argue that background intensity changes should not be ignored and are useful in interpreting scattering from these nano-scale materials.

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Growth kinetics of silver chloride precipitation in a Na2O-B2O3 glass investigated by means of small-angle X-ray scattering and transmission electron microscopy

Journal of Materials Science ◽

10.1007/bf00356458 ◽

1996 ◽

Vol 31 (16) ◽

pp. 4333-4346 ◽

Cited By ~ 5

Author(s):

U. Lembke ◽

K. Grosse ◽

R. Pascova ◽

I. Gutzow ◽

O. Becker ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Growth Kinetics ◽

Small Angle ◽

Silver Chloride ◽

X Ray ◽

X Ray Scattering ◽

Transmission Electron ◽

Kinetics Of ◽

B2o3 Glass

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Growth Kinetics of Polyelectrolyte Complexes Formed from Oppositely-Charged Homopolymers Studied by Time-Resolved Ultra-Small-Angle X-ray Scattering

The Journal of Physical Chemistry Letters ◽

10.1021/acs.jpclett.6b02957 ◽

2017 ◽

Vol 8 (4) ◽

pp. 737-741 ◽

Cited By ~ 22

Author(s):

Rintaro Takahashi ◽

Theyencheri Narayanan ◽

Takahiro Sato

Keyword(s):

Growth Kinetics ◽

Small Angle ◽

Time Resolved ◽

Polyelectrolyte Complexes ◽

X Ray ◽

X Ray Scattering ◽

Oppositely Charged ◽

Kinetics Of ◽

Ray Scattering

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Investigations of the Growth Kinetics of Capped CdSe and CdS Nanocrystals by a Combined Use of Small Angle X-ray Scattering and Other Techniques

Chemistry - An Asian Journal ◽

10.1002/asia.200800119 ◽

2008 ◽

Vol 3 (8-9) ◽

pp. 1435-1442 ◽

Cited By ~ 11

Author(s):

Neenu Varghese ◽

Kanishka Biswas ◽

C. N. R. Rao

Keyword(s):

Growth Kinetics ◽

Small Angle ◽

X Ray ◽

Cds Nanocrystals ◽

X Ray Scattering ◽

Combined Use ◽

Kinetics Of ◽

Ray Scattering

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Growth Kinetics of Gold Nanocrystals: A Combined Small-Angle X-Ray Scattering and Calorimetric Study

Small ◽

10.1002/smll.200700937 ◽

2008 ◽

Vol 4 (5) ◽

pp. 649-655 ◽

Cited By ~ 38

Author(s):

Kanishka Biswas ◽

Neenu Varghese ◽

Chintamani N. R. Rao

Keyword(s):

Growth Kinetics ◽

Small Angle ◽

Calorimetric Study ◽

Gold Nanocrystals ◽

X Ray ◽

X Ray Scattering ◽

Kinetics Of ◽

Ray Scattering

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Growth kinetics of ω particles in β-Ti matrix studied by in situ small-angle X-ray scattering

Acta Materialia ◽

10.1016/j.actamat.2015.08.014 ◽

2015 ◽

Vol 100 ◽

pp. 126-134 ◽

Cited By ~ 9

Author(s):

J. Šmilauerová ◽

P. Harcuba ◽

D. Kriegner ◽

M. Janeček ◽

V. Holý

Keyword(s):

Growth Kinetics ◽

Small Angle ◽

X Ray ◽

X Ray Scattering ◽

Kinetics Of ◽

Ray Scattering

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Growth kinetics of humins studied via X-ray scattering

Green Chemistry ◽

10.1039/c9gc03961a ◽

2020 ◽

Vol 22 (7) ◽

pp. 2301-2309

Author(s):

Ziwei Cheng ◽

Konstantinos A. Goulas ◽

Natalia Quiroz Rodriguez ◽

Basudeb Saha ◽

Dionisios G. Vlachos

Keyword(s):

Growth Kinetics ◽

Small Angle ◽

Volume Fraction ◽

Number Concentration ◽

X Ray ◽

X Ray Scattering ◽

Brönsted Acid ◽

Acid Catalyzed ◽

Kinetics Of ◽

Ray Scattering

We use ultra-small-angle X-ray scattering to investigate the evolution of size, morphology, volume fraction and number concentration of humins formed during the Brønsted acid catalyzed dehydration of fructose to 5-hydroxymethylfurfural (HMF).

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