Effect of Modification by WTP-08 on Dispersity of Nanosized CalciumCarbonate and Its Mechanism

2011 ◽  
Vol 688 ◽  
pp. 51-56
Author(s):  
Hao Ding ◽  
Bai Kun Wang ◽  
Ning Liang ◽  
Kun Liu
Keyword(s):  
Free Energy ◽  
Calcium Carbonate ◽  
Surface Energy ◽  
Chemical Method ◽  
Interfacial Free Energy ◽  
Free Energies ◽  
Polar Medium ◽  
Polar Media ◽  
Thermodynamic Effect ◽  
Interfacial Free Energies

The dispersity of nanosized calcium carbonate modified by alkyl amine dimethyl phosphonic acid (WTP-08) through mechano-chemical method in different media was investigated. The modification mechanism was investigated by analyzing the surface energy and its thermodynamic effect on dispersity of nanosized calcium carbonate. The results show that the free energies of nanosized calcium carbonate modified by WTP-08 and its interfacial free energies in air and non-polar media decrease significantly, while the interfacial free energy in water increases remarkably. It can be concluded that modification by WTP-08 improves the dispersion tendency of nanosized calcium carbonate in air and non-polar medium, while it decreases in water. Therefore, modification by WTP-08 makes the dispersity of nanosized calcium carbonate increase in air and non-polar medium and decrease in water.

Quantitative Evaluation of the Interfacial Free Energies at A Solid-Liquid Lamellar Eutectic Interface

1981 ◽  
Vol 12 ◽  
Author(s):  
W. F. Kaukler ◽  
J. W. Rutter
Keyword(s):  
Free Energy ◽  
Solid Phase ◽  
Interfacial Free Energy ◽  
Eutectic System ◽  
Liquid Interfaces ◽  
Free Energies ◽  
Two Phases ◽  
Interfacial Free Energies ◽  
The Individual ◽  
Solid Liquid

The solid-liquid interfacial free energies of each of the individual phases comprising the eutectic system, Carbon Tetrabromide-Hexachloroethane, were measured as a function of composition using a “grain boundary groove” technique. Thermodynamic data were combined with groove shape measurements made from high resolution optical photomicrographs of the solid-liquid interfaces to give the interfacial free energy data. An interfacial free energy balance at the eutectic trijunction was performed to obtain all the forces acting on that point. The three interphase interfacial free energies at the eutectic trijunctions as well as a solid-solid phase boundary torque were evaluated.It was found that the solid-liquid interfacial free energies of the two phases of the eutectic could be evaluated from photomicrographs of growing or stationary eutectic interfaces. In addition, it was found that for a substantial range of freezing conditions the eutectic interface shape can be predicted from a knowledge of the interfacial free energies alone.

Determining Interfacial Free Energies from Creep Experiments on Silver-Iron Multilayers

1994 ◽  
Vol 356 ◽  
Author(s):  
D. Josell ◽  
Z.L. Wang
Keyword(s):  
Thin Films ◽  
Free Energy ◽  
Boundary Diffusion ◽  
Interfacial Free Energy ◽  
Multilayer Thin Films ◽  
Free Energies ◽  
Diffusion Controlled ◽  
Interfacial Free Energies ◽  
Over Time ◽  
Microstructural Data

AbstractExperiments were conducted on multilayer thin films to determine the free energies associated with silver/iron interfaces. Creep studies determined the loads for which the multilayers neither shrank nor stretched over time. Microstructural data was used with the zero creep loads in a model for grain boundary diffusion controlled creep in multilayers to determine the interfacial free energy.

Interactions of components and elements of the surface free energy at interfaces

1991 ◽  
Vol 56 (2) ◽  
pp. 277-295 ◽  
Author(s):  
Jan Kloubek
Keyword(s):  
Free Energy ◽  
Surface Free Energy ◽  
Polar Phase ◽  
Free Energies ◽  
Dispersion Component ◽  
Liquid Systems ◽  
Interfacial Free Energies ◽  
Total Surface Free Energy ◽  
Solid Liquid ◽  
New Hypothesis

A new hypothesis is suggested for the evaluation of the components (γd and γab) and the elements (γa and γb) of the surface free energy. The respective equations are introduced for the interactions at interfaces between a non-polar acid and non-polar base, a polar phase and non-polar acid or base, and two polar phases. The dispersion component, γd, equals the total surface free energy of non-polar phases. However, they can interact at the interface as an acid or a base through their single permanent elements γa or γb, respectively. Otherwise, induced elements γia and γib can also be effective. The surface free energy of polar phases is additively composed of the dispersion, γd, and acid-base components, γab = 2(γaγb)1/2. The proposed equation are verified using the known values of the surface and interfacial free energies for the liquid-liquid systems and they are applied to the solid-liquid interfaces. The values of the elements are determined for water, γwa = 67.7 and γwb = 10.6 mJ/m2, and for other liquids, such as glycerol, formamide, mercury, benzene, diethyl ether and trichloromethane.

Determination of Ag/Co Interfacial Free Energies by Biaxial Zero Creep Experiments

2003 ◽  
Vol 778 ◽  
Author(s):  
Bing An ◽  
Tong-jun Zhang ◽  
Chao Yuan ◽  
Kun Cui ◽  
Wei Zhang
Keyword(s):  
Residual Stress ◽  
Plastic Deformation ◽  
Free Energy ◽  
Room Temperature ◽  
Multilayer Films ◽  
Free Energies ◽  
Grain Distribution ◽  
Interfacial Free Energies

AbstractTo measure the Ag/Co interfacial free energies, biaxial zero creep experiments were performed on Ag/Co multilayer films deposited on the Si (111) wafers. As the samples were heated from room temperature to 450°C, the residual stress in films, which was in situ monitored by substrate curvature technique, decayed gradually to zero due to the increasing plastic deformation in films. After held for several hours at 450°C, they reached a zero creep state while the equilibrium stresses were measured. The annealed element layers were immiscible, and exhibited the column grain distribution and (111) preferred orientations. Based on the Josell model, the free energy of Ag/Co (111) interfaces at 450°C was found to be 1.02 ± 0.17 J/m2.

Formation of Surface Structure in Vulcanizates and Surface Structure Changes in Air

1995 ◽  
Vol 68 (1) ◽  
pp. 97-109 ◽  
Author(s):  
Kunio Mori ◽  
Kentaro Kanae ◽  
Hidetoshi Hirahara ◽  
Yoshiyuki Oishi
Keyword(s):  
Free Energy ◽  
Surface Structure ◽  
Surface Free Energy ◽  
High Surface ◽  
Surface Region ◽  
Interfacial Free Energy ◽  
Chemical Compositions ◽  
Free Energies ◽  
Dry Air ◽  
Structure Changes

Abstract The formation theory of surface structure during vulcanization was developed on the basis of an interfacial concept. The theory showed the chemical compositions of polar and nonpolar components on the vulcanizate surface to be determined as an excess interfacial free energy between rubber compounds and molds decreases. The surface free energies of molds reflected clearly the corresponding surface free energy of vulcanizates prepared from copolymers and polar polymers. Nonpolar polymers were not influenced by the surface free energies of molds. The surface free energies of vulcanizates decreased slightly with the concentration of network chains owing to the entropy of rubber segments. The surface free energies of molds affected the chemical compositions at the topmost surface region to the upper surface region on vulcanizates. NBR vulcanizates with high surface free energy increased the contact angle of water after standing in dry air. In the dry air environment, topmost surface layer nitrile groups were buried in the bulk of NBR vulcanizates and butadiene units subsequently overturn to the topmost, layer. In this case, the vulcanizate surface chemical composition was influenced only at the topmost surface region. ESCA spectra N1s peak intensities on NBR vulcanizates was consistent with these observation.

Surface Energy Driven Crystallization of Amorphous Pd81si19

1997 ◽  
Vol 481 ◽  
Author(s):  
Gerhard Schumacher ◽  
Rajeshwar P. Wahi
Keyword(s):  
Crystal Growth ◽  
Thermal Treatment ◽  
Surface Energy ◽  
Thermodynamic Model ◽  
Crystallization Front ◽  
In Situ Tem ◽  
Free Energies ◽  
Electrochemical Polishing ◽  
Interfacial Free Energies

ABSTRACTIn-situ TEM investigations during thermal treatment of amorphous Pd81Si19 have been performed. It was found that crystalline nuclei are formed near the perforation edge of the hole produced by electrochemical polishing. After impinging with neighboring crystals, a crystallization front formed which was aligned parallel to the perforation edge. The crystallization front moved in the direction perpendicular to the perforation edge. Crystal growth was found to proceed faster in thinner parts of the specimen than in thicker parts. The results are described qualitatively within a thermodynamic model taking into account volume-, surface- and interfacial free energies and an appropriate specimen geometry.

scholarly journals Thermodynamic and Kinetic Parameters for Calcite Nucleation on Peptoid and Model Scaffolds - a Step Toward Nacre Mimicry.

2019 ◽  
Author(s):  
Anne Rath Nielsen ◽  
Stanislav Jelavic ◽  
Daniel Murray ◽  
Behzad Rad ◽  
Martin Andersson ◽  
...  
Keyword(s):  
Free Energy ◽  
Calcium Carbonate ◽  
Kinetic Parameters ◽  
Functional Groups ◽  
Driving Forces ◽  
Interfacial Free Energy ◽  
Nucleation Theory ◽  
Dynamic Force ◽  
Thermodynamic And Kinetic Parameters ◽  
Insight Into

To establish an approach for a bulk upscaling of a composit material consisting of calcium carbonate and tunable peptoids we here combined three distinct approaches to thoroughly access the underlying kinetic and thermodynamic driving forces for CaCO3 formation on peptoid polymers. We derived the net interfacial free energy for calcite formation on the nanosheets and self-assemblage monolayers of the sheets constituent functional groups (carboxyl, amine and a 1:1 mix) using: nucleation experiments, dynamic force spectroscopy and theoretical modeling (COSMO-RS). We applied nucleation theory to the results and obtain insight into conditions were we can obtain favorable nucleation conditions on the polymers in a highly controlled manner.

scholarly journals Microscopic origin of the effect of substrate metallicity on interfacial free energies

2021 ◽  
Vol 118 (50) ◽  
pp. e2108769118
Author(s):  
Laura Scalfi ◽  
Benjamin Rotenberg
Keyword(s):  
Free Energy ◽  
Surface Force ◽  
Interfacial Free Energy ◽  
Fermi Model ◽  
Thomas Fermi ◽  
Metallic Character ◽  
Ionic Systems ◽  
Interfacial Free Energies ◽  
Dynamics Simulations ◽  
Microscopic Origin

We investigate the effect of the metallic character of solid substrates on solid–liquid interfacial thermodynamics using molecular simulations. Building on the recent development of a semiclassical Thomas–Fermi model to tune the metallicity in classical molecular dynamics simulations, we introduce a thermodynamic integration framework to compute the evolution of the interfacial free energy as a function of the Thomas–Fermi screening length. We validate this approach against analytical results for empty capacitors and by comparing the predictions in the presence of an electrolyte with values determined from the contact angle of droplets on the surface. The general expression derived in this work highlights the role of the charge distribution within the metal. We further propose a simple model to interpret the evolution of the interfacial free energy with voltage and Thomas–Fermi length, which allows us to identify the charge correlations within the metal as the microscopic origin of the evolution of the interfacial free energy with the metallic character of the substrate. This methodology opens the door to the molecular-scale study of the effect of the metallic character of the substrate on confinement-induced transitions in ionic systems, as reported in recent atomic force microscopy and surface force apparatus experiments.

scholarly journals Thermodynamic and Kinetic Parameters for Calcite Nucleation on Peptoid and Model Scaffolds - a Step Toward Nacre Mimicry.

2019 ◽  
Author(s):  
Anne Rath Nielsen ◽  
Stanislav Jelavic ◽  
Daniel Murray ◽  
Behzad Rad ◽  
Martin Andersson ◽  
...  
Keyword(s):  
Free Energy ◽  
Calcium Carbonate ◽  
Kinetic Parameters ◽  
Functional Groups ◽  
Driving Forces ◽  
Interfacial Free Energy ◽  
Nucleation Theory ◽  
Dynamic Force ◽  
Thermodynamic And Kinetic Parameters ◽  
Insight Into

To establish an approach for a bulk upscaling of a composit material consisting of calcium carbonate and tunable peptoids we here combined three distinct approaches to thoroughly access the underlying kinetic and thermodynamic driving forces for CaCO3 formation on peptoid polymers. We derived the net interfacial free energy for calcite formation on the nanosheets and self-assemblage monolayers of the sheets constituent functional groups (carboxyl, amine and a 1:1 mix) using: nucleation experiments, dynamic force spectroscopy and theoretical modeling (COSMO-RS). We applied nucleation theory to the results and obtain insight into conditions were we can obtain favorable nucleation conditions on the polymers in a highly controlled manner.

Wood Surface Energy and Time Dependence of Wettability: A Comparison of Different Wood Surfaces Using an Acid-Base Approach

Holzforschung ◽  
2001 ◽  
Vol 55 (4) ◽  
pp. 433-440 ◽  
Author(s):  
Milojka Gindl ◽  
Gerhard Sinn ◽  
Alexander Reiterer ◽  
Stefanie Tschegg
Keyword(s):  
Free Energy ◽  
Surface Energy ◽  
Cell Layer ◽  
Contact Angles ◽  
Time Behaviour ◽  
Free Energies ◽  
Acid Base ◽  
Base Approach ◽  
Wood Surfaces ◽  
Lower Contact

Summary Using four different wood species, the wetting behaviour of sanded wood surfaces was compared with that of microtomed surfaces. Sanding caused lower contact angles and lower total surface free energies. Electron donor components were considered to be responsible for the observed changes according to the applied acid-base approach. The time behaviour of sanded surfaces differed from the microtomed reference, insofar as the volume of a deposited drop of water decreased very rapidly as soon as it was applied, indicating fast penetration into the wood. A qualitative analysis by SEM revealed a heavily torn upper-most cell layer on sanded surfaces, which was assumed to be responsible for the increased surface free energy and enhanced penetration.

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