Solid–Solid Crystal Transitions (? to ?) in Poly(hexamethylene carbonate) and Poly(octamethylene carbonate)

Phase transitions in biogenic amorphous calcium carbonate.

Crystalline biominerals do not resemble faceted crystals. Current explanations for this property involve formation via amorphous phases. Using X-ray absorption near-edge structure (XANES) spectroscopy and photoelectron emission microscopy (PEEM), here we examine forming spicules in embryos of Strongylocentrotus purpuratus sea urchins, and observe a sequence of three mineral phases: hydrated amo...

Determination of Crystal Growth Rate and Morphology of Barium Carbonate Crystals in a Semi-batch Crystallizer

A semi-batch crystallization system is used to determine growth kinetics and morphology of barium carbonate crystals, under a constant pH value and constant temperature in the various relative supersaturations. Results show that crystal growth rate satisfies a first-order kinetic expression at high relative supersaturation, while at relative supersaturation values lower than 3,  the k...

Crystal structure of a di­aryl carbonate: 1,3-phenyl­ene bis­(phenyl carbonate)

The whole mol-ecule of the title compound, C20H14O6, is generated by mirror symmetry, the mirror bis-ecting the central benzene ring. The carbonate groups adopt an s-cis-s-cis conformation, with torsion angles of 58.7 (2) and 116.32 (15)°. The crystal structure of 1,3-phenyl-ene bis-(phenyl carbonate) contains no strong hydrogen bonds, though weak C-H⋯O and offset π-π inter-actions are observed...

Lanthanum carbonate

Carbonate Advisor

Quantitative producibility and textural analysis for carbonate reservoirs ft 1 0 ft3/ft3