Eocene shales metamorphosed by a naturally ignited coal seam in the Powder River Basin, Wyoming record a continuum of mineralogic and textural changes from relatively unaltered shale to melt developed during pyrometamorphism. Samples collected along a section 2 m in length, corresponding to a temperature range of approximately 1300 ~ C, were examined optically and by XRD, SEM, and STEM. The low...

The synthesis of a new resorbable porous bioactive silica-calcium phosphate composite (SCPC) that can be used as a tissue-engineering scaffold for bone regeneration is described. The effects of chemical composition and thermal treatment on crystallization and the mechanism of phase transformation in SCPC were evaluated. In the silica-rich samples, beta-rhenanite (beta-NaCaPO(4)) and alpha-crist...

In this Article, we reported the synthesis of a crystalline CO2–SiO2 solid solution by reacting carbon dioxide and silica in a laser-heated diamond anvil cell at pressures between 16 and 22GPa and temperatures greater than 4,000K, and showed that carbon enters silica. We have now reanalysed all our X-ray diffraction patterns, in particular those at room pressure where potential volatile compone...

Abstract BN/La-Al-Si-O composite ceramics were fabricated by hot-pressed sintering using hexagonal boron nitride (h-BN), lanthanum oxide (La 2 O 3 ), aluminia (Al and amorphous silica (SiO ) as the raw materials. The effects of temperature on microstructural evolution, bulk density, apparent porosity, mechanical properties h-BN investigated. results indicated that La-Al-Si-O liquid phase was fo...

Abstract We identified dmisteinbergite, the rare trigonal polymorph of CaAl2Si2O8, for first time in high-grade metamorphic rocks. Dmisteinbergite occurs as a crystallization product silicate melt inclusions (nanogranitoids) garnet from three host rocks with different protoliths and re-equilibration conditions, i.e., 1.0 to 4.5 GPa. Raman spectra compositions dmisteinbergite here investigated a...

Extreme conditions permit unique materials to be synthesized and can significantly update our view of the periodic table. In the case of group IV elements, carbon was always considered to be distinct with respect to its heavier homologues in forming oxides. Here we report the synthesis of a crystalline CO2-SiO2 solid solution by reacting carbon dioxide and silica in a laser-heated diamond anvil...

Abstract Red Mud is a bauxite solid waste which dangerous for the environment because of its alkalinity (10-13). With very high pH, it can interfere with hydrological conditions areas that are directly affected by mud. Efforts to utilize red mud have use-value been widely carried out. consists Gibbsite, Hematite and Cristobalite. The main ingredients Fe 2 O 3 , Al SiO still be utilized 44.66%, ...