Hydrothermal Synthesis of Lithium Zinc Phosphates: Structural Investigation of Twinned α-Li4Zn(PO4)2 and a High Temperature Polymorph β-Li4Zn(PO4)2

Carbon doped, visible light active and ordered mesoporous TiO2–SiO2 nanocomposites have been successfully synthesized via one step high temperature (180 °C) hydrothermal technology.

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Molecular and Crystal Structure of a High-Temperature Polymorph of Chitosan from Electron Diffraction Data. [Erratum to document cited in CA121:303404]

Macromolecules ◽

10.1021/ma00108a080 ◽

1995 ◽

Vol 28 (4) ◽

pp. 1332-1332

Author(s):

Karim Mazeau ◽

William T. Winter ◽

Henri Chanzy

Keyword(s):

Crystal Structure ◽

High Temperature ◽

Electron Diffraction ◽

Diffraction Data ◽

Molecular And Crystal Structure ◽

Electron Diffraction Data ◽

High Temperature Polymorph

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High-Temperature, High-Pressure Hydrothermal Synthesis, Crystal Structure, Thermal Stability, and Solid State NMR Spectroscopy of an Aluminum Borate, Ba[AlB4O8(OH)]

Inorganic Chemistry ◽

10.1021/acs.inorgchem.7b02855 ◽

2018 ◽

Vol 57 (3) ◽

pp. 1545-1549 ◽

Cited By ~ 3

Author(s):

Chun-Chi Peng ◽

Hsin-Kuan Liu ◽

Kwang-Hwa Lii

Keyword(s):

Crystal Structure ◽

Thermal Stability ◽

High Pressure ◽

High Temperature ◽

Hydrothermal Synthesis ◽

Solid State ◽

Nmr Spectroscopy ◽

Solid State Nmr ◽

Aluminum Borate ◽

High Temperature High Pressure

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Crystallization kinetics of BaO–Al2O3–SiO2 glasses

Journal of Materials Research ◽

10.1557/jmr.1989.1257 ◽

1989 ◽

Vol 4 (5) ◽

pp. 1257-1265 ◽

Cited By ~ 80

Author(s):

Narottam P. Bansal ◽

Mark J. Hyatt

Keyword(s):

High Temperature ◽

Ceramic Composites ◽

X Ray Diffraction ◽

Aluminosilicate Glasses ◽

Structural Applications ◽

Barium Aluminosilicate ◽

Kinetics Of ◽

High Temperature Polymorph ◽

Large Volume Change ◽

Glass Compositions

Barium aluminosilicate glasses are being investigated as matrix materials in high-temperature ceramic composites for structural applications. Kinetics of crystallization of two refractory glass compositions in the barium aluminosilicate system have been studied by differential thermal analysis (DTA), x-ray diffraction (XRD), and scanning electron microscopy (SEM). From variable heating rate DTA, the crystallization activation energies for glass compositions (wt. %) 10BaO–38Al2O3–51SiO2–1MoO3 (glass A) and 39BaO–25Al2O3–35SiO2–1MoO3 (glass B) were determined to be 553 and 558 kJ/mol, respectively. On thermal treatment, the crystalline phases in glasses A and B were identified as mullite (3Al2O3 · 2SiO2) and hexacelsian (BaO · Al2O3 · 2SiO2), respectively. Hexacelsian is a high-temperature polymorph which is metastable below 1590 °C. It undergoes structural transformation into the orthorhombic form at ∼300 °C accompanied by a large volume change which is undesirable for structural applications. A process needs to be developed where stable monoclinic celsian, rather than hexacelsian, precipitates out as the crystal phase in glass B.

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