Could Mesophases Play a Role in the Nucleation and Polymorph Selection of Zeolites?

2018 ◽  
Vol 140 (47) ◽  
pp. 16071-16086 ◽  
Author(s):  
Abhinaw Kumar ◽  
Andrew H. Nguyen ◽  
Rita Okumu ◽  
Tricia D. Shepherd ◽  
Valeria Molinero
Keyword(s):  
Polymorph Selection ◽  
Selection Of

scholarly journals Polymorph Selection of ROY by Flow-Driven Crystallization

Crystals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 351 ◽  
Author(s):  
Ziemecka ◽  
Gokalp ◽  
Stroobants ◽  
Brau ◽  
Maes ◽  
...  
Keyword(s):  
Radial Flow ◽  
Outer Edge ◽  
Local Concentration ◽  
Equilibrium Flow ◽  
Confined Space ◽  
Flow Conditions ◽  
Flow Rates ◽  
Polymorph Selection ◽  
Displacement Pattern ◽  
Selection Of

The selection of polymorphs of the organic compound 5-methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile, ROY, is studied experimentally in the confined space between two horizontal glass plates when an acetone solution of ROY of variable concentration is injected at a variable flow rate into water. Depending on the local concentration within the radial flow, a polymorph selection is observed such that red prisms are favored close to the injection center while yellow needles are the preferred polymorph close to the edge of the injected ROY domain. At larger flow rates, a buoyancy-driven instability induces stripes at the outer edge of the displacement pattern, in which specific polymorphs are seen to crystallize. Our results evidence the possibility of a selection of ROY polymorph structures in out-of-equilibrium flow conditions.

Understanding Polymorph Selection of Sulfamerazine in Solution

2019 ◽  
Vol 19 (12) ◽  
pp. 6925-6934 ◽  
Author(s):  
Chengxiang Liu ◽  
Fengjuan Cao ◽  
Samir A. Kulkarni ◽  
Geoffrey P. F. Wood ◽  
Erik E. Santiso
Keyword(s):  
Polymorph Selection ◽  
Selection Of

Polymorph selection of magnesium under different pressures: a simulation study

2021 ◽  
Author(s):  
Wei Liu ◽  
Boqiang Wu ◽  
Ze'an Tian ◽  
Yunfei Mo ◽  
Tingfei Xi ◽  
...  
Keyword(s):  
Simulation Study ◽  
Polymorph Selection ◽  
Selection Of

POLYMORPH SELECTION OF CALCIUM CARBONATE BY THE MORPHOLOGY OF BIOMACROMOLECULES: FROM ARAGONITE, VATERITE TO CALCITE

2009 ◽  
Vol 23 (31n32) ◽  
pp. 3695-3706 ◽  
Author(s):  
JUNWU XIAO ◽  
YINGCHUN ZHU ◽  
JIANHUI YUAN ◽  
QICHAO RUAN ◽  
YI ZENG ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
General Interest ◽  
Hexagonal Prism ◽  
Polymorph Selection ◽  
Chitosan Gel ◽  
Selection Of

The selective polymorph synthesis of aragonite, vaterite and calcite was done by changing the conformation of chitosan molecules. Aragonite crystals in hexagonal prism-like shape were obtained in chitosan precipitates, vaterite crystals in hexagonal symmetrical plate-like shape were prepared in chitosan gel, and calcite nanoparticles were obtained in chitosan sol. The phenomenon of polymorph selection of biominerals by the morphology of biomacromolecules indicates that the studies on the relation between biominerals and biomacromelecules have general interest not only in bionics, but also in biometrics and related fields.

Cognitive gadgets and cognitive priors

2019 ◽  
Vol 42 ◽  
Author(s):  
Gian Domenico Iannetti ◽  
Giorgio Vallortigara
Keyword(s):  
Cognitive Neuroscience ◽  
Selection Of

Abstract Some of the foundations of Heyes’ radical reasoning seem to be based on a fractional selection of available evidence. Using an ethological perspective, we argue against Heyes’ rapid dismissal of innate cognitive instincts. Heyes’ use of fMRI studies of literacy to claim that culture assembles pieces of mental technology seems an example of incorrect reverse inferences and overlap theories pervasive in cognitive neuroscience.

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

Measurements of the Cape Astrometric Survey of the Southern Hemisphere

1978 ◽  
Vol 48 ◽  
pp. 515-521
Author(s):  
W. Nicholson
Keyword(s):  
Southern Hemisphere ◽  
Automatic Measuring ◽  
Measuring Machine ◽  
Final Selection ◽  
Selection Of

SummaryA routine has been developed for the processing of the 5820 plates of the survey. The plates are measured on the automatic measuring machine, GALAXY, and the measures are subsequently processed by computer, to edit and then refer them to the SAO catalogue. A start has been made on measuring the plates, but the final selection of stars to be made is still a matter for discussion.

Application of Improved Voltage Compensation in the SEM to Imaging of Organic Materials

1973 ◽  
Vol 31 ◽  
pp. 444-445
Author(s):  
P.J. Killingworth ◽  
M. Warren
Keyword(s):  
Electron Beam ◽  
Organic Materials ◽  
Operating Parameters ◽  
Low Density ◽  
Beam Diameter ◽  
Incident Electron Beam ◽  
Specimen Material ◽  
Voltage Compensation ◽  
Selection Of ◽  
Scanning Electron

Ultimate resolution in the scanning electron microscope is determined not only by the diameter of the incident electron beam, but by interaction of that beam with the specimen material. Generally, while minimum beam diameter diminishes with increasing voltage, due to the reduced effect of aberration component and magnetic interference, the excited volume within the sample increases with electron energy. Thus, for any given material and imaging signal, there is an optimum volt age to achieve best resolution.In the case of organic materials, which are in general of low density and electric ally non-conducting; and may in addition be susceptible to radiation and heat damage, the selection of correct operating parameters is extremely critical and is achiev ed by interative adjustment.

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