Characterization of the temperature and humidity-dependent phase diagram of amorphous nanoscale organic aerosols

2017 ◽  
Vol 19 (9) ◽  
pp. 6532-6545 ◽  
Author(s):  
Nicholas E. Rothfuss ◽  
Markus D. Petters
Keyword(s):  
Phase Diagram ◽  
Amorphous Phase ◽  
Phase State ◽  
Organic Aerosols ◽  
State Diagram ◽  
Model Calculations ◽  
Temperature And Humidity

The amorphous phase state diagram for sucrose aerosol is obtained from a mix of measurements and model calculations.

TEM Characterization of Pseudotetragonal Mullite

2001 ◽  
Vol 7 (S2) ◽  
pp. 426-427
Author(s):  
Bradley R. Johnson ◽  
Waltraud M. Kriven
Keyword(s):  
Phase Diagram ◽  
Spatial Relationship ◽  
Equilibrium Structure ◽  
Lattice Parameters ◽  
Orthorhombic Structure ◽  
Containerless Processing ◽  
Rich Phase ◽  
Tem Characterization ◽  
Solution Field

Mullite (3Al2O3•2SiO2) exists in a solid solution field (∼57-63 mol% Al2O3) as the only stable compound in the Al2O3•SiO2 phase diagram at ambient pressures. Equilibrium 3:2 mullite has an orthorhombic structure with b>a (o-mullite). However, when initially crystallized from molecularly mixed, 3:2 precursors at temperatures < 1200°C, the first phase that forms has lattice parameters with a ≈b. This structure is often termed pseudotetragonal mullite (pt-mullite), since even when the ‘a’ and ‘b’ lattice parameters are identical, they are symmetrically independent. Pseudotetragonal mullite has been shown to contain approx. 70 mol% Al2O3. with increasing time and temperature, the structure gradually assimilates the residual SiO2, and the lattice parameters change, such that by 1400°C, the material has attained its equilibrium structure and composition.TEM was used to determine the spatial relationship between the crystalline phase and the residual, amorphous, SiO2-rich phase in pt-mullite. The starting materials were quenched, 3:2 mullite beads and fibers (made by containerless processing).

Phase diagram, crystal growth and characterization of Mn-substituted ZnGeAs2 system

2008 ◽  
Vol 69 (2-3) ◽  
pp. 408-410 ◽  
Author(s):  
Hiroaki Matsushita ◽  
Masaki Watanabe ◽  
Akinori Katsui
Keyword(s):  
Phase Diagram ◽  
Crystal Growth

Phase state diagram of a poly(amic acid)–solvent–nonsolvent system

2018 ◽  
Vol 67 (10) ◽  
pp. 1831-1837 ◽  
Author(s):  
A. A. Shcherbina ◽  
V. K. Gerasimov ◽  
T. P. Semenov ◽  
A. E. Chalykh
Keyword(s):  
Phase State ◽  
State Diagram ◽  
Amic Acid

scholarly journals Weathering features of a remineralizer in soil under different land uses

2021 ◽  
Vol 56 ◽  
Author(s):  
Rafael Cipriano da Silva ◽  
Edilene Pereira Ferreira ◽  
Antonio Carlos de Azevedo
Keyword(s):  
Amorphous Phase ◽  
Ammonium Oxalate ◽  
Total Content ◽  
Sodium Dithionite ◽  
Land Uses ◽  
Elephant Grass ◽  
X Ray ◽  
Time Periods ◽  
Gains And Losses

Abstract The objective of this work was to analyze the mineralogical, morphological, and compositional modifications resulting from the weathering of diabase grains buried into soil under different land uses for up to 378 days. Samples of comminuted diabase were put into polyester bags and buried into soil under corn crop, elephant grass, and woods, being unburied and evaluated after four time periods. The samples of the remineralizer (RM) were analyzed by X-ray diffractometry, total chemical analysis, scanning electron microscopy, and Al (Ald and Alo) and Fe (Fed and Feo) contents extracted by sodium dithionite-citrate-bicarbonate (DCB) and ammonium oxalate (AAO) solutions. Plagioclases and pyroxenes were the most weathered minerals in all three land uses and showed the same pattern of elemental gains and losses. The characterization of Fe and Al solubility in DCB and AAO showed that the greatest change in these elements was from the lithogenic and crystalline to the pedogenic and amorphous phase, when compared with their total content. Plagioclases and pyroxenes were the most weathered minerals, and Fe and Al show a great transfer from the crystalline to the amorphous phase, with values up to 26 and 175, respectively, for the ratios between bags with RM/Feo and RM-control and bags with RM/Alo and RM-control.

scholarly journals Thermodynamic characterization of Mexico City aerosol during MILAGRO 2006

2007 ◽  
Vol 7 (3) ◽  
pp. 9203-9233 ◽  
Author(s):  
C. Fountoukis ◽  
A. Nenes ◽  
A. Sullivan ◽  
R. Weber ◽  
T. VanReken ◽  
...  
Keyword(s):  
Gas Phase ◽  
Mexico City ◽  
Thermodynamic Equilibrium ◽  
Phase State ◽  
Molar Ratio ◽  
Inorganic Species ◽  
Equilibrium Calculations ◽  
Thermodynamic Equilibrium Model ◽  
Thermodynamic Equilibrium Calculations

Abstract. Fast measurements of aerosol and gas-phase constituents coupled with the ISORROPIA-II thermodynamic equilibrium model are used to study the partitioning of semivolatile inorganic species and phase state of Mexico City aerosol sampled at the T1 site during the MILAGRO 2006 campaign. Overall, predicted semivolatile partitioning agrees well with measurements. PM2.5 is insensitive to changes in ammonia but is to acidic semivolatile species. Semi-volatile partitioning equilibrates on a timescale between 6 and 20 min. When the aerosol sulfate-to-nitrate molar ratio is less than 1, predictions improve substantially if the aerosol is assumed to follow the deliquescent phase diagram. Treating crustal species as "equivalent sodium" (rather than explicitly) in the thermodynamic equilibrium calculations introduces important biases in predicted aerosol water uptake, nitrate and ammonium; neglecting crustals further increases errors dramatically. This suggests that explicitly considering crustals in the thermodynamic calculations are required to accurately predict the partitioning and phase state of aerosols.

Characterization of the amorphous phase in nylon 6 fibers by X-ray diffraction

1991 ◽  
Vol 47 (0) ◽  
pp. 185-197 ◽  
Author(s):  
N. S. Murthy ◽  
S. T. Correale ◽  
R. A. F. Moore
Keyword(s):  
Amorphous Phase ◽  
Nylon 6 ◽  
X Ray Diffraction ◽  
X Ray

Molecular characterization of size-segregated organic aerosols in the urban boundary layer in wintertime Beijing by FT-ICR MS

2021 ◽  
Author(s):  
Qiaorong Xie ◽  
Sihui Su ◽  
Shuang Chen ◽  
Qiang Zhang ◽  
Siyao Yue ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Size Distribution ◽  
Molecular Characterization ◽  
Organic Aerosols ◽  
Urban Boundary Layer ◽  
Vertical Profiles ◽  
Unique Information ◽  
Ft Icr Ms ◽  
Ft Icr

Our study provides unique information on the vertical profiles and size distribution of urban organic aerosols by FT-ICR MS.

Characterization of phases in the Zr–Nb–Fe ternary system at the Zr–Nb rich side of the phase diagram

2020 ◽  
Vol 534 ◽  
pp. 152142
Author(s):  
Fei Long ◽  
M. Griffiths ◽  
Z. Yao ◽  
M.R. Daymond
Keyword(s):  
Phase Diagram ◽  
Ternary System ◽  
Rich Side
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