2001 FallMeeting
Using integrated approaches, we are investigating the kinetics and thermodynamics of calcite growth to decipher mechanisms of biomineral excepting one, show evidence of halite dissolution with elevated Na andCl concentrations; nine of these samples also show evidence of gypsum dissolution, with … View This Document

Calcium Carbonate – Wikipedia, The Free Encyclopedia
However, modern manufactured chalk is mostly gypsum, hydrated calcium sulfate CaSO 4 ·2H 2 O. Calcium carbonate is a main source for growing Seacrete where the initial state is the acid solution with no Ca 2+ (not taking into account possible CO 2 dissolution) and the final state is the solution with … Read Article

Hydration Of Anhydrite Of gypsum (CaSO
Hydration of anhydrite of gypsum (CaSO 4.II) in a ball mill Keywords: Anhydrite; Hydration; Kinetics; Sulfate, Modeling They considered the hydration as dissolution– nucleation–growth process, in which nucleation was … Read Content

Influence Of Tertiary Alkanolamines On The Hydration Of …
July 27-29, 2009 International Summit on Cement Hydration Kinetics, Quebec, PQ 3 Bibliography * S. Chaberek& A. E. Martell takes several days [in first day] * Proposed that sulfates adsorb onto C3A surfaces and slow its dissolution rate very quickly after wetting * Exhaustion of gypsum causes rapid … Content Retrieval

Topics In Cement And gypsum Research
As the starting material for the gypsum plasterboard production, hemihydrate occurs in two formations of α- and β-type, which Within CEMHYD3D the kinetics are mainly regulated by the dissolution and nucleation chances and the number of diffusion steps. … Document Viewer

Formation Of Natural gypsum Megacrystals In Naica, Mexico
Sulfur and oxygen isotopic compositions of gypsum crystals are compatible with growth from solutions resulting from dissolution of anhydrite previously prec ipitated during (4) Gypsum nucleation kinetics imply induction times longer than 1 m.y. for the typical temperature (54 °C) and ~1 k.y … Document Viewer

Peter C. Lichtner & Qinjun K Los Alamos National Laboratory …
PCL-17 Linear Kinetics: Stationary State Dissolution Dual continuum prediction bars CO 2 + Mg + SO 4 + Calcite → Dolomite + Gypsum t = 10 5 steps t = 2×10 5 steps t = 4×10 5 steps Calcite Dolomite Gypsum 1 … Visit Document

CRYSTALLISATION AND MORPHOLOGY OF GYPSUM STUDIED BY …
CRYSTALLISATION AND MORPHOLOGY OF GYPSUM STUDIED BY SYNCHROTRON X-RAY DIFFRACTION AND SCANNING were performed to investigate the possibility of recording both the crystallisation kinetics and the The relative X-ray intensities were utilised to follow the dissolution of hemihydrate and formation of … View Doc

Solubility – Wikipedia, The Free Encyclopedia
In practice, it means that the amount of solute in a solution is not always determined by its thermodynamic solubility, but may depend on kinetics of dissolution (or precipitation). … Read Article

Activities Of Foreign Researchers
Kinetics of gypsum dissolution and its solubility in aqueous media. Arid Land Research Center, Tottori University, Tottori Japan. 1998. 8. Sodic soil reclamation under semi arid and arid conditions. … Access Doc

Speleogenesis In Carbonate Rocks
Because of differences in molar volume, the precipitated calcite usually does not occupy all the porosity generated by dissolution of gypsum or anhydrite. Dissolution kinetics of calcium carbonate in sea water; IV: Theory of calcite dissolution. … Access Full Source

Modelingthedissolutionofcalcitecoupledtogypsumprecipitationin …
Flow-through experiments are carried out to study the kinetics of the dissolution of calcite coupled to the precipitation of gypsum at atmospheric PCO2. … Document Retrieval

Carbonate And Gypsum
Determination of gypsum has generally been done by dissolution and mea-surement of Ca and/or SOa- in a dilute extract. Dissolution kinetics of calcium carbonate in seatwater. IV Theory of calcite dissolution. … Fetch Doc

Q.L. Yu; H.J.H. Brouwers; A.C.J. De Korte Gypsum Hydration: A …
Ultrasonic results indicate gypsum hydration reaction consists of two stages: the dissolution of hemihydrate in the first stage and the nucleation and precipitation of Crystallization kinetics of gypsum from dense suspension of hemihydrate water. … Access This Document

L¨osungskinetik Von Gips Und Anhydrit – Dissertation Zur …
Abstract The dissolution kinetics of gypsum and anhydrite have been measured under va rious conditions. Far from equilibrium they are determined by mixed kinetics, … Access Document

Formation Of Natural gypsum Megacrystals In Naica, Mexico – †2H
From solutions resulting from dissolution of anhydrite previously pre cipitated during late hydrothermal mineralization, suggesting that these megacrystals formed by a self-feeding mechanism driven by a solution-mediated, anhydrite-gypsum phase transition. Nucleation kinetics calculations based on … Retrieve Document

Impacts Of Nanosilver On Microbial Activity In Wetlands And …
Therefore, convection is present in addition to dissolution and diffusion and the dissolution kinetics is hindered by the diffusion and convection kinetics, all three being of the same order of magnitude. As a proof, we have exhaustively collected the dissolution rates of gypsum in water, measured by … Content Retrieval

SEMI-BATCH CRYSTALLIZATION OF GYPSUM FROM CALCITE AND …
SEMI-BATCH CRYSTALLIZATION OF GYPSUM FROM CALCITE Compton, R.; Prout, K.; Payne, R. Gypsum overgrowths passivate calcite to acid attack. J. Colloid Interface Sci. 1997 , 192 , 207-214. [2] Chou, L.; Garrells, M.; Wollast, R. Comparative study of the kinetics and mechanism of dissolution of Carbonate … Retrieve Full Source

Redalyc. Dissolution Of Minor Sulphides Present In A Pyritic …
Dissolution kinetics. INTRODUCTION The sludge produced by the mine at Aznalcóllar (SW Spain) is made up of a mixture of different sulphides. lack of total aqueous sulphur might be due to the precipitation of secondary sulphur-phases (anglesite, cerussite, native sulphur, gypsum and … Doc Retrieval

Experimental Techniques For Cement Hydration Studies
The overall kinetics of cement hydration involves the dissolution of several solid reactant phases, e.g., alite (an impure form of tricalcium silicate, C3S 1), C3A and gypsum (CSH … Read Content