Proposal method for a triaxial test on sands improved by microbial carbonate precipitation

undrained triaxial shear behavior of grouted carbonate sands

the effects of cementation and the physical properties of grains on the shear behavior of grouted sands are investigated in this paper. the consolidated-undrained triaxial shear behavior of three grouted carbonate sands with different physical properties, including particle size distribution, particle shape and void ratio, was studied. two sands were obtained from the north shores of the persia...

Strain-specific ureolytic microbial calcium carbonate precipitation.

During a study of ureolytic microbial calcium carbonate (CaCO(3)) precipitation by bacterial isolates collected from different environmental samples, morphological differences were observed in the large CaCO(3) crystal aggregates precipitated within bacterial colonies grown on agar. Based on these differences, 12 isolates were selected for further study. We hypothesized that the striking differ...

A Simple and Fast Method for Field Calibration of Triaxial Gyroscope by using Accelerometer

Synthesis of BiFeO3 by carbonate precipitation

Magnetoelectric multiferroic BiFeO3 (BFO) was synthesized by a simple carbonate precipitation technique of metal nitrate solutions. X-ray powder diffraction and thermo-gravimetric analysis (TGA) revealed that the precipitate consists of an intimate mixture of crystalline bismuth carbonate and an amorphous hydroxide of iron. The precipitate yielded BiFeO3 at an optimal calcination temperature of...

Carbonate Precipitation Driven by Clay Leachates on Early Mars

Introduction: Secondary carbonate minerals produced by low temperature aqueous processes [1] in the martian meteorite ALH 84001 are evidence of an early active hydrosphere on Mars when they were formed ~3.9 Ga ago [2]. Further evidence for an early hydrosphere includes orbital and surface observations of diverse alteration mineral assemblages [e.g. 3-5] and fluvial geomorphology [6]. While carb...