The role of magmatic reaction, diffusion, and annealing in the evolution of coronitic microstructure in troctolitic gabbro from Risör, Norway: a discussion

1986 ◽  
Vol 50 (357) ◽  
pp. 469-473 ◽  
Author(s):  
J. R. Ashworth
Keyword(s):  
Solid State ◽  
Open System ◽  
Local Equilibrium ◽  
Reaction Diffusion ◽  
One Dimension ◽  
System Behaviour ◽  
Diffusion Controlled

AbstractThe data of Joesten (1986) are re-interpreted. The petrography of the coronas is not consistent with magrnatic origin. Both microstructural types described by Joesten (1986), here re-named ‘columnar’ and ‘tabular’, formed by solid-state replacement of plagioclase and of adjacent olivine or ilmenite. Tabular microstructures are not annealed, but result from overgrowth or epitaxy of amphibole and pyroxene on pre-existing grains. Since the diffusion-controlled models of Joesten (1986) can account for major aspects of the coronas, it seems possible that a slightly modified, less simplified theory might explain them fully. Open-system behaviour must be admitted, with some constraints provided by symplectites. It may also be necessary to develop the theory in more than one dimension, and to allow for departures from local equilibrium at layer boundaries.

A complex corona between olivine and plagioclase from the Jotun Nappe, Norway, and the diffusion modelling of multimineralic layers

1992 ◽  
Vol 56 (385) ◽  
pp. 511-525 ◽  
Author(s):  
J. R. Ashworth ◽  
J. J. Birdi ◽  
T. F. Emmett
Keyword(s):  
Electron Microscopy ◽  
Diffusion Coefficients ◽  
Local Equilibrium ◽  
Mineral Layer ◽  
Small Diffusion ◽  
Phase Rule ◽  
Transmission Electron ◽  
Diffusion Controlled ◽  
State Diffusion

AbstractCoronas containing Ca-amphibole with aluminous minerals have been characterised optically and by scanning electron microscopy, analytical transmission electron microscopy and electron-probe microanalysis. The layers nearest to plagioclase are amphibole + epidote + kyanite, followed by amphibole + epidote + staurolite + spinel. These assemblages are consistent with waterundersaturated conditions, possibly at lower metamorphic grade than the commoner assemblage amphibole + spinel. Observed mineral proportions and compositions were used in a seven-layer model of steady-state, diffusion-controlled growth with local equilibrium. This model is not fully realistic, because the observed amphibole is strongly zoned from tschermakitic to actinolitic away from plagioclase, suggesting disequilibrium. However, the four-mineral layer has been successfully modelled assuming local equilibrium, with diffusion coefficients Lii larger for i = FeO and MgO than for SiO2, AlO3/2, CaO and FeO3/2. Retarded grain-boundary diffusion of the latter components is explicable by crystal-chemical effects. The number of minerals per layer is constrained by a modified form of the metasomatic phase rule of Korzhinskii, with the role of 'inert' components played by relatively immobile ones (having relatively small fluxes and relatively small diffusion coefficients).

scholarly journals Understanding solid-state processing of pharmaceutical cocrystals via milling: Role of tablet excipients

2021 ◽  
Vol 601 ◽  
pp. 120514 ◽  
Author(s):  
Rahamatullah Shaikh ◽  
Saeed Shirazian ◽  
Sarah Guerin ◽  
Eoin Sheehan ◽  
Damien Thompson ◽  
...  
Keyword(s):  
Solid State ◽  
Pharmaceutical Cocrystals ◽  
Tablet Excipients ◽  
State Processing

A Dual-Wavelength Electrochromic Film Based on Pt(II) Complex for Optical Modulation at Telecommunication Wavelength and Dark Solid-State Display Device

2021 ◽  
Author(s):  
Qiaozhen Pi ◽  
Dongqin Bi ◽  
dongfang qiu ◽  
Hongwei Wang ◽  
Xinfeng Cheng ◽  
...  
Keyword(s):  
Solid State ◽  
Dual Wavelength ◽  
Optical Modulation ◽  
Display Device ◽  
Redox Behaviour ◽  
Diffusion Controlled ◽  
Telecommunication Wavelength

A cyclometalated platinum phenylacetylide [(L)Pt(C≡C-ph)] {L = 4-[p-(diphenylamino)phenyl]-6-phenyl-2,2’-bipyridine} has been successfully synthesized and characterized. And its oxidative electropolymerization film with a non-diffusion controlled redox behaviour and an inverse dependence of...

The Role of Protons and Formation Cu(NH3)2+ During Ammonia-Assisted Solid-State Ion Exchange of Copper(I) Oxide into Zeolites

2018 ◽  
Vol 62 (1-4) ◽  
pp. 100-107 ◽  
Author(s):  
Peter N. R. Vennestrøm ◽  
Lars F. Lundegaard ◽  
Christoffer Tyrsted ◽  
Dmitriy A. Bokarev ◽  
Alina I. Mytareva ◽  
...  
Keyword(s):  
Solid State ◽  
Ion Exchange

Role of solid-state structure in propene hydrogenation with nickel catalysts

1990 ◽  
Vol 86 (4) ◽  
pp. 739 ◽  
Author(s):  
Giovanni Carturan ◽  
Stefano Enzo ◽  
Renzo Ganzerla ◽  
Maurizio Lenarda ◽  
Roberto Zanoni
Keyword(s):  
Solid State ◽  
Nickel Catalysts ◽  
State Structure ◽  
Solid State Structure

scholarly journals Electrochemiluminescence Study of Europium (III) Complex with Coumarin3-Carboxylic Acid

2008 ◽  
Vol 2008 ◽  
pp. 1-6 ◽  
Author(s):  
Stefan Lis ◽  
Krzysztof Staninski ◽  
Tomasz Grzyb
Keyword(s):  
Aqueous Solution ◽  
Spectral Analysis ◽  
Energy Transfer ◽  
Solid State ◽  
Carboxylic Acid ◽  
Elemental Analysis ◽  
Aluminium Electrode ◽  
The Eu

The europium (III) complex of coumarin-3-carboxylic acid (C3CA) has been prepared and characterized on the basis of elemental analysis, IR, and emission (photoluminescence and electrochemiluminescence) spectroscopy. The synthesised complex having a formula Eu was photophysically characterized in solution and in the solid state. Electrochemiluminescence, ECL, of the system containing the Eu(III)/C3CA complex was studied using an oxide-covered aluminium electrode. The goal of these studies was to show the possibility of the use of electrochemical excitation of the Eu(III) ion in aqueous solution for emission generation. The generated ECL emission was very weak, and therefore its measurements and spectral analysis were carried out with the use of cut-off filters method. The studies proved a predominate role of the ligand-to-metal energy transfer (LMET) in the generated ECL.

Role of Nuclei in Liesegang Pattern Formation: Insights from Experiment and Reaction-Diffusion Simulation

2018 ◽  
Vol 122 (6) ◽  
pp. 3669-3676 ◽  
Author(s):  
Masaki Itatani ◽  
Qing Fang ◽  
Kei Unoura ◽  
Hideki Nabika
Keyword(s):  
Pattern Formation ◽  
Reaction Diffusion ◽  
Diffusion Simulation

Joining of Ti3SiC2 with Ti–6Al–4V Alloy

2002 ◽  
Vol 17 (1) ◽  
pp. 52-59 ◽  
Author(s):  
N.F. Gao ◽  
Y. Miyamoto
Keyword(s):  
Solid State ◽  
Rate Constant ◽  
Liquid State ◽  
Parabolic Rate Constant ◽  
Diffusion Path ◽  
Solid State Diffusion ◽  
Diffusion Controlled ◽  
State Diffusion ◽  
Rate Controlled ◽  
Higher Temperature

The joining of a Ti3SiC2 ceramic with a Ti–6Al–4V alloy was carried out at the temperature range of 1200–1400 °C for 15 min to 4 h in a vacuum. The total diffusion path of joining was determined to be Ti3SiC2/Ti5Si3Cx/Ti5Si3Cx + TiCx/TiCx/Ti. The reaction was rate controlled by the solid-state diffusion below 1350 °C and turned to the liquid-state diffusion controlled with a dramatic increase of parabolic rate constant Kp when the temperature exceeded 1350 °C. The TiCx tended to grow at the boundarywith the Ti–6Al–4V alloy at a higher temperature and longer holding time. TheTi3SiC2/Ti–6Al–4V joint is expected to be applied to implant materials.

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