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# The Gibbs–Thomson Effect, in common [[physics]] usage, refers to variations in vapor pressure or chemical potential across a curved surface or interface. The existence of a positive interfacial energy will increase the energy required to form small particles with high curvature, and these particles will exhibit an increased vapor pressure. See [[Ostwald–Freundlich equation]]. | |||
# More specifically, the Gibbs–Thomson effect refers to the observation that small crystals are in equilibrium with their liquid melt at a lower temperature than large crystals. In cases of confined geometry, such as liquids contained within porous media, this leads to a depression in the freezing point / melting point that is inversely proportional to the pore size, as given by the Gibbs–Thomson equation. | |||
==Introduction== | |||
# The technique is closely related to using gas adsorption to measure pore sizes, but uses the Gibbs–Thomson equation rather than the [[Kelvin equation]]. They are both particular cases of the Gibbs Equations of [[Josiah Willard Gibbs]]: the Kelvin equation is the constant temperature case, and the Gibbs–Thomson equation is the constant pressure case.<ref name="NMRC_Review_(MWS)">{{cite journal | |||
| title = Nuclear Magnetic Resonance Cryoporometry | |||
| journal = Phys. Rep. | |||
| year = 2008 | |||
| volume = 461 | |||
| pages = 1–36 | |||
| first1 = J. | last1 = Mitchell | |||
| first2 = J. Beau W. | last2 = Webber | |||
| first3 = J.H. | last3 = Strange | |||
| doi = 10.1016/j.physrep.2008.02.001 | |||
| bibcode=2008PhR...461....1M | |||
}}</ref> | |||
# This behaviour is closely related to the capillary effect and both are due to the change in bulk free energy caused by the curvature of an interfacial surface under tension.<ref name="Ref:Defay:1951reprinted1966:STension">{{Citation | |||
| title = Surface tension and adsorption | |||
| publisher = Longmans Green and Co. (London) | |||
| year = 1951 reprinted 1966 | |||
| last1 = Defay | first1 = R. | |||
| last2 = Prigogine | first2 = I. | |||
| last3 = Bellemans | first3 = A. | |||
| last4 = Everett | first4 = D.H.}}</ref><ref name="Ref:Gregg+Sing:1967:Adsorp">{{Citation | |||
| title = Adsorption surface area and porosity | |||
| publisher = Academic Press (London) | |||
| year = 1967 | |||
| edition = second edition | |||
| last1 = Gregg | first1 = S.J. | |||
| last2 = Sing | first2 = K.S.W. | |||
}}</ref> | |||
# The original equation only applies to isolated particles, but with the addition of surface interaction terms (usually expressed in terms of the contact wetting angle) can be modified to apply to liquids and their crystals in porous media. As such it has given rise to various related techniques for measuring pore size distributions, see [[Themoporometry and Cryoporometry]]. | |||
# The Gibbs–Thomson effect lowers both melting and freezing point, and also raises boiling point. However, simple cooling of an all-liquid sample usually leads to a state of non-equilibrium [[super cooling]] and only eventual non-equilibrium freezing. To obtain a measurement of the equilibrium freezing event, it is necessary to first cool enough to freeze a sample with excess liquid outside the pores, then warm the sample until the liquid in the pores is all melted, but the bulk material is still frozen. Then, on re-cooling the equilibrium freezing event can be measured, as the external ice will then grow into the pores.<ref name="Ref:Petrov+Furo:2006:warm+cool">{{Citation | |||
| last1 = Petrov | first1 = O. | |||
| last2 = Furo | first2 = I. | |||
| title = Curvature-dependent metastability of the solid phase and the freezing-melting hysteresis in pores | |||
| journal = Phys. Rev. | |||
| year = 2006 | |||
| volume = 73 | |||
| pages = 7 | |||
| issue = 1 | |||
| month = Jan | |||
| issn = 1539-3755 | |||
}}</ref><ref name="Ref:Webber:2007:MRPM-8:Bologna">{{Citation | |||
| last1 = Webber | first1 = J. Beau W. | |||
| last2 = Anderson | first2 = Ross | |||
| last3 = Strange | first3 = John H. | |||
| last4 = Tohidi | first4 = Bahman | |||
| title = Clathrate formation and dissociation in vapour/water/ice/hydrate systems in SBA-15 Sol-Gel and CPG porous media as probed by NMR relaxation novel protocol NMR Cryoporometry Neutron Scattering and ab-initio quantum-mechanical molecular dynamics simulation. | |||
| journal = Magn. Reson. Imaging | |||
| year = 2007 | |||
| volume = 25 | |||
| pages = 533–536 | |||
| issue = 4 | |||
| publisher = Elsevier (Netherlands) | |||
| doi = 10.1016/j.mri.2006.11.022 | pmid=17466781 | |||
}}</ref> | |||
This is in effect an "ice intrusion" measurement (''cf.'' [[Porosimetry|Mercury Intrusion]]), and as such in part may provide information on pore throat properties. The melting event can be expected to provide more accurate information on the pore body. | |||
==Gibbs–Thomson equation for particles== | |||
# For an isolated spherical solid particle of diameter <math>x</math> in its own liquid, the Gibbs-Thomson Equation for the structural melting point depression can be written:<ref name="Ref:Jackson+McKenna:1990">{{Citation | |||
| title = The melting behavior of organic materials confined in porous solids | |||
| last1 = Jackson | first1 = C. L. | |||
| last2 = McKenna | first2 = G. B. | |||
| journal = J. Chem. Phys. | |||
| year = 1990 | |||
| volume = 93 | |||
| pages = 9002–9011 | |||
| issue = 12 | |||
| month = Dec | |||
| issn = 0021-9606 | |||
|doi=10.1063/1.459240 | |||
|bibcode = 1990JChPh..93.9002J }}</ref> | |||
# <math>\Delta\,T_m(x)=T_{mB}-T_m(x)=T_{mB}\frac{4\sigma\,_{sl}}{H_f\rho\,_sx}</math> | |||
# Where: | |||
::T<sub>mB</sub>=Bulk Melting temperature | |||
::σ<sub>sl</sub> = solid–liquid interface energy (per unit area) | |||
::H<sub>f</sub> = bulk enthalpy of fusion (per gram of material) | |||
::ρ<sub>s</sub> = density of solid | |||
The "4" in the above equation comes from the spherical geometry of the solid-liquid interface. | |||
Note: <math>x</math> is used for the pore size rather than <math>d</math> for a number of reasons : | |||
::It is consistent with the original published notation. | |||
::The equation can be used with planar geometry (with a change of constant). | |||
::For consistency with the related [[Strange–Rahman–Smith equation]] where the symbol <math>d</math> is used for the [[differential operator]]. | |||
==Gibbs–Thomson equation for liquids in pores== | |||
Very similar equations may be applied to the growth and melting of crystals in the confined geometry of porous systems. However the geometry term for the crystal-liquid interface may be different, and there may be additional surface energy terms to consider, which can be written as a wetting angle term <math>cos\phi\,</math>. The angle is usually considered to be near 180°. In cylindrical pores there is some evidence that the freezing interface may be spherical, while the melting interface may be cylindrical, based on preliminary measurements for the measured ratio for <math>\Delta\,T_f / \Delta\,T_m</math> in cylindrical pores.<ref name="Ref:Webber:2010">{{Citation | |||
| author = Webber J. B. W. | |||
| title = Studies of nano-structured liquids in confined geometries and at surfaces | |||
| journal = Progress In Nuclear Magnetic Resonance Spectroscopy | |||
| year = 2010 | |||
| volume = 56 | |||
| pages = 78–93 | |||
| issue = 1 | |||
| doi = 10.1016/j.pnmrs.2009.09.001 | |||
}}</ref> | |||
Thus for a spherical interface between a non-wetting crystal and its own liquid, in an infinite cylindrical pore of diameter <math>x</math>, the structural melting point depression | |||
is given by:<ref>The geometry of the crystal–liquid interface determines the value of the constant in the Gibbs–Thomson equation – the conventional "4" only applies to a spherical interface in a cylindrical pore.<!--- [[Gibbs-Thomson relation]] what about it? ---></ref> | |||
<math>\Delta\,T_m(x) = T_{mB}-T_m(x)= - T_{mB}\frac{4\sigma\,_{sl}cos\phi\,}{H_f\rho\,_sx}</math> | |||
==Simplified Gibbs-Thomson equation== | |||
The Gibbs–Thomson equation may be written in a compact form:<ref name="NMRC_(SRS)">{{Citation | |||
| title = Characterization of Porous Solids by NMR | |||
| journal = Phys. Rev. Lett. | |||
| year = 1993 | |||
| volume = 71 | |||
| pages = 3589–3591 | |||
| issue = 21 | |||
| month = Nov | |||
| last1 = Strange | first1 = J.H. | |||
| last2 = Rahman | first2 = M. | |||
| last3 = Smith | first3 = E.G. | |||
| doi = 10.1103/PhysRevLett.71.3589 | |||
| url = http://link.aps.org/doi/10.1103/PhysRevLett.71.3589 | |||
| pmid=10055015 | |||
| bibcode=1993PhRvL..71.3589S | |||
}}</ref> | |||
<math>\Delta\,T_m(x)= \frac{k_{GT}}{x}</math> | |||
where the Gibbs-Thomson Coefficient <math> k_{GT}</math> assumes different values for different liquids<ref name="Ref:Jackson+McKenna:1990"/><ref name="Ref:Webber:2010" /> and different interfacial geometries (spherical/cylindrical/planar).<ref name="Ref:Webber:2010" /> | |||
In more detail:,<ref name="NMRC_Review_(MWS)" /><ref name="Ref:Webber:2007:Plastic-Ice:NDC+NMR">{{Citation | |||
| title = Plastic ice in confined geometry: The evidence from neutron diffraction and NMR relaxation. | |||
| journal = J. Phys.: Condens. Matter | |||
| year = 2007 | |||
| volume = 19 | |||
| pages = 415117 (12pp) | |||
| doi = 10.1088/0953-8984/19/41/415117 | |||
| url = http://stacks.iop.org/0953-8984/19/415117 | |||
| last1 = Webber | first1 = J. Beau W. | |||
| last2 = Dore | first2 = John C. | |||
| last3 = Strange | first3 = John H. | |||
| last4 = Anderson | first4 = Ross | |||
| last5 = Tohidi | first5 = Bahman | |||
|bibcode = 2007JPCM...19O5117W }}</ref> | |||
<math>\Delta\,T_m(x)= \frac{k_{GT}}{x} = \frac{k_g \, k_s \, k_i}{x}</math> | |||
Where : <math>k_g</math> is a geometric constant dependent on the interfacial shape, | |||
:: <math>k_s</math> is a constant involving parameters specific to the crystalline solid of solid–liquid system, and | |||
:: <math>k_i</math> is an interfacial energy term. | |||
==History== | |||
By 1906, the German physical chemist Friedrich Wilhelm Küster (1861-1917) had predicted that since the vapor pressure of a finely pulverized volatile solid is greater than the vapor pressure of the bulk solid, then the melting point of the fine powder should be lower than that of the bulk solid.<ref>Friedrich Wilhelm Küster (1906) ''Lehrbuch der allgemeinen physikalischen und theoretischen Chemie'' … [Textbook of general physical and theoretical chemistry … ] (Heidelberg, Germany: Carl Winter, 1906), v.1, p. 189. The relevant passage is reprinted on page 189 of volume 1 of the 1913 edition: [http://babel.hathitrust.org/cgi/pt?id=wu.89097922835;view=1up;seq=209 § 127. Schmelzen feinster Pulver.] (Melting of the finest powder). From page 189: ''"Folglich ist die Schmelztemperatur des Pulvers, t<sub>1</sub>°, niedriger als die der Kristalle, t°. Der Unterschied ist jedoch so gering, daß er noch nicht zur Beobachtung gelangt ist (vgl. weiter unter §. 131)."'' (Consequently, the melting temperature of the powder, t<sub>1</sub>°, is lower than that of the [bulk] crystal, t°. However, the difference is so small that it still hasn't been observed (compare §. 131 below).)</ref> Investigators such as the Russian physical chemist Pavel Nikolaevich Pavlov (1872-1953) searched for and eventually observed such melting point depression. They recognized that the depression occurred when the change in surface energy was significant compared to the latent heat of the phase transition, which condition obtained in the case of very small particles.<ref>See, for example: | |||
* Pawlow, P. N. (1909) "Über die Abhängigkeit des Schmelzpunktes von der Oberflächenenergie eines festen Korpers" (On the dependency of the melting point on the surface energy of a solid body), ''Zeitschrift für physikalische Chemie'', '''65''' : 1-35 ; 545-548. | |||
* Pawlow, P. N. (1910) "Ueber den Einfluss der Oberfläche einer festen Phase auf die latente Wärme und die Temperatur des Schmelzens" (On the effect of the surface of a solid phase on the latent heat and the temperature of melting), ''Zeitschrift für Chemie und Industrie der Kolloide'', '''7''' : 37-39.</ref> | |||
Neither [[Josiah Willard Gibbs]] nor William Thomson ([[William Thomson, 1st Baron Kelvin|Lord Kelvin]]) derived the Gibbs–Thomson equation.<ref>Jeong-Myeong Ha, ''Crystallization and Thermotropic Properties of Organic Solids in Nanoscopic Reactors'', Ph.D. thesis: University of Minnesota, 2006, [http://books.google.com/books?id=cxaN_Xul-c4C&pg=PA26#v=onepage&q&f=false pages 26-28].</ref> Also, although many sources claim that British physicist [[J. J. Thomson]] derived the Gibbs–Thomson equation in 1888, he did not.<ref>Sir Joseph John Thomson derived Kelvin's equation ([http://books.google.com/books?id=EAc6AAAAMAAJ&pg=PA163#v=onepage&q&f=false page 163]) and the depression of the melting point of ice by pressure ([http://books.google.com/books?id=EAc6AAAAMAAJ&pg=PA258#v=onepage&q&f=false page 258]), but he did not derive the Gibbs-Thomson equation. However, on [http://books.google.com/books?id=EAc6AAAAMAAJ&pg=PA251#v=onepage&q&f=false pages 251-252], Thomson considered the effects of temperature and surface tension on the solubility of salts in spherical droplets, and he obtained an equation for that phenomenon which has a form similar to that of the Gibbs-Thomson equation. See: Thomson, J.J., ''Applications of dynamics to physics and chemistry'' (London, England: Macmillan and Co., 1888).</ref> Early in the 20th century, investigators derived precursors of the Gibbs–Thomson equation.<ref>See: | |||
* Pawlow, P. N. (1909) "Über die Abhängigkeit des Schmelzpunktes von der Oberflächenenergie eines festen Korpers" (On the dependency of the melting point on the surface energy of a solid body), ''Zeitschrift für physikalische Chemie'', '''65''' : 545-548. [Note: "P. N. Pawlow" was a Russian physical chemist, Pavel Nikolaevich Pavlov (1872-1953).] | |||
* Tammann, Gustav H.J.A. (1920) [http://babel.hathitrust.org/cgi/pt?id=uc1.b3959131;view=1up;seq=480 "Über eine Methode zur Bestimmung der Abhängigkeit des Schmelzpunktes einer Kristallamelle von ihrer Dicke"] (On a method for the determination of the dependency of the melting point of a crystal plate on its thickness), ''Zeitschrift für anorganische und allgemeine Chemie'', '''110''' (1) : 166-168.</ref> However, in 1920, the Gibbs-Thomson equation was first derived in its modern form by two researchers working independently: Friedrich Meissner, a student of the Estonian-German physical chemist [[Gustav Heinrich Johann Apollon Tammann|Gustav Tammann]], and Ernst Rie (1896-1921), an Austrian physicist at the University of Vienna.<ref>Meissner, F. (1920) [http://babel.hathitrust.org/cgi/pt?id=uc1.b3959131;view=1up;seq=483 "Mitteilungen aus dem Institut für physikalische Chemie der Universität Göttingen. Nr. 8. Über den Einfluß der Zerteilung auf die Schmelztemperatur"] (Communications from the Institute for Physical Chemistry of the University of Göttingen. Nr. 8. On the influence of division on the melting point), ''Zeitschrift für anorganische und allgemeine Chemie'', '''110''' (1) : 169-186. Meißner presents a form of the Gibbs-Thomson equation as equation (2) on page 174.</ref><ref>Note: | |||
* Ernst Rie first published the Gibbs-Thomson equation in 1920 in his dissertation for a degree from the University of Vienna. | |||
* Extracts from that dissertation were published in 1923 in: Ernst Rie (1923) "Über die Einfluss der Oberflächenspannung auf Schmelzen und Gefrieren" (On the influence of surface tension on melting and freezing), ''Zeitschrift für physikalische Chemie'', '''104''' : 354-362. | |||
* A draft version of Rie's article in the ''Zeitschrift für physikalische Chemie'' appeared in: Ernst Rie (1920) Vorläufige Meitteilung: "Einfluß der Oberflächenspannung auf Schmelzen und Gefrieren" (Preliminary notice: Influence of surface tension on melting and freezing), ''Anzeiger der Akademie der Wissenschaften in Wien: Mathematisch-naturwissenschaftliche Klasse'' (Gazette of the Philosophical Academy of Vienna: mathematical-scientific section), '''57''' : 137-139. Available on-line at: [http://www.landesmuseum.at/pdf_frei_remote/AAWW_57_0001-0318.pdf State Museum of Austria.] The Gibbs-Thomson equation appears on page 138.</ref> These early investigators did not call the relation the "Gibbs-Thomson" equation. That name was in use by 1910 or earlier;<ref>See, for example: | |||
* [[Archibald Macallum|A.B. Macallum]] (October 7, 1910) [http://books.google.com/books?id=GpICAAAAYAAJ&pg=PA449#v=onepage&q&f=false "Surface tension in relation to cellular processes,"] ''Science'', '''32''' (823) : 449-458. After explaining the Gibbs-Thomson principle (and its origin) on page 455, he uses the term "Gibbs-Thomson principle" on page 457: "This determination is based on the deduction from the Gibbs-Thomson principle that, where in a cell an inorganic element or compound is concentrated, the surface tension at the point is lower than it is elsewhere in the cell." | |||
:See also: A.B. Macallum (October 14, 1910) [http://books.google.com/books?id=GpICAAAAYAAJ&pg=PA492#v=onepage&q&f=false "Surface tension in relation to cellular processes. II,"] ''Science'', '''32''' (824) : 492-502. | |||
* Duncan A. MacInnes and Leon Adler (1919) "Hydrogen overvoltage," ''Journal of the American Chemical Society'', '''41''' (2) : 194-207. "By the Gibbs-Thompson law, substances that lower the surface tension are those which are adsorbed." | |||
* Shanti Swarup Bhatnagar and Dasharath Lal Shrivastava (1924) "The optical inactivity of the active sugars in the adsorbed state -- a contribution to the chemical theory of adsorption. I," ''Journal of Physical Chemistry'', '''28''' (7) : 730-743. From page 730: "There are at present three well-known theories regarding the mechanism of protective action of colloids: (1) That the protecting agent concentrates at the interface of the colloid particles and the dispersion medium according to [the] Gibbs-Thomson law, …" | |||
* Ashutosh Ganguli (1930) "On the adsorption of gases by solids," ''Journal of Physical Chemistry'', '''34''' (3) : 665-668. From page 665: "The intimate connection of adsorption with surface tension was shown long before by Gibbs, subsequently known as the Gibbs-Thomson equation."</ref> it originally referred to equations concerning the adsorption of solutes by interfaces between two phases — equations that Gibbs and then J. J. Thomson derived.<ref>[[Frederick G. Donnan|Frederick George Donnan]] and Arthur Erich Haas, ed.s, ''A Commentary on the Scientific Writings of J. Willard Gibbs'', vol. 1 (New Haven, Connecticut: Yale University Press, 1936), page 544. In 1878, Gibbs published an equation concerning the adsorption of a solute by an interface between two phases, and in 1888, J.J. Thomson published an equation concerning the same phenomenon, which he'd derived via a different method but which superficially resembled Gibbs' result. Apparently both equations were eventually known as "the Gibbs-Thomson equation". From page 544: "There is a rather prevalent impression that the two equations are the same, but that is not so; and both on grounds of priority and because of the wider scope of Gibbs' result, there is no justification for the use of the name "Gibbs-Thomson equation" which one sometimes meets in the literature, although it is doubtless true that Thomson's work was independently carried out."</ref> Hence, in the name "Gibbs-Thomson" equation, "Thomson" refers to J. J. Thomson, not William Thomson (Lord Kelvin). | |||
In 1871, William Thomson published an equation describing capillary action and relating the curvature of a liquid-vapor interface to the vapor pressure:<ref>Sir William Thomson (1871) [http://books.google.com/books?id=ZeYXAAAAYAAJ&pg=PA448#v=onepage&q&f=false "On the equilibrium of vapour at a curved surface of liquid,"] ''Philosophical Magazine'', series 4, '''42''' (282) : 448-452. See equation (2) on page 450.</ref> | |||
<math> p(r_1 , r_2) = P - \frac {2 \gamma\, \rho\, _{vapor} } {(\rho\,_{liquid} - \rho\,_{vapor})}\left ( \frac {1}{r_1} + \frac {1}{r_2}\right ) </math> | |||
where | |||
: <math> p(r) </math> = vapor pressure at a curved interface of radius <math> r </math> | |||
: <math> P </math> = vapor pressure at a flat interface (<math> r = \infty </math>) = <math> p_{eq} </math> | |||
: <math> \gamma </math> = surface tension | |||
: <math> \rho\, _{vapor} </math> = density of vapor | |||
: <math> \rho\, _{liquid} </math> = density of liquid | |||
:<math> r_1 </math> , <math> r_2 </math> = radii of curvature along the principal sections of the curved interface. | |||
In his dissertation of 1885, Robert von Helmholtz (son of German physicist [[Hermann von Helmholtz]]) showed how the [[Ostwald-Freundlich equation]] | |||
<math> \ln \left ( \frac {p(r)} {P} \right ) = \frac {2 \gamma V_{molecule} P} {k_B T r}</math> | |||
could be derived from Kelvin's equation.<ref>Robert von Helmholtz (1886) [http://books.google.com/books?id=9xVbAAAAYAAJ&pg=PA508#v=onepage&q&f=false "Untersuchungen über Dämpfe und Nebel, besonders über solche von Lösungen"] (Investigations of vapors and mists, especially of such things from solutions), ''Annalen der Physik'', '''263''' (4) : 508-543. On pages 523-525, Robert von Helmholtz converts Kelvin's equation to the Ostwald-Freundlich equation.</ref><ref>Robert von Helmholtz’s derivation of the Ostwald-Freundlich equation from Kelvin’s equation is reproduced (in English) on the "Talk" page of Wikipedia's article on the Ostwald-Freundlich equation.</ref> The Gibbs–Thomson equation can then be derived from the Ostwald-Freundlich equation via a simple substitution using the integrated form of the [[Clausius-Clapeyron relation]]:<ref>This derivation of the Gibbs-Thomson equation appears on pages 417-418 of: James E. McDonald (December 1953) "Homogeneous nucleation of supercooled water drops," ''Journal of Meteorology'', '''10''' : 416-433. Available on-line at: [http://puhep1.princeton.edu/~mcdonald/JEMcDonald/mcdonald_jm_10_416_53.pdf Princeton.edu]</ref> | |||
<math>\ln \left ( \frac {P_2}{P_1} \right ) = \frac {L}{R} \left ( \frac {1}{T_1} - \frac {1}{T_2} \right ).</math> | |||
The Gibbs–Thomson equation can also be derived directly from Gibbs' equation for the energy of an interface between phases.<ref>Josiah Willard Gibbs (1878) "On the equilibrium of heterogeneous substances," ''Transactions of the Connecticut Academy of Arts and Sciences'', '''3''' : 343-524. The equation for the energy that's required to create a surface between two phases appears on [http://books.google.com/books?id=ZsQAAAAAYAAJ&pg=PA483#v=onepage&q&f=false page 483]. Reprinted in: Josiah Willard Gibbs with Henry Andrews Bumstead and Ralph Gibbs van Name, ed.s, ''The Scientific Papers of J. Willard Gibbs, …'', vol. 1, (New York, New York: Longmans, Green and Co., 1906), [http://books.google.com/books?id=8RhWAAAAMAAJ&pg=PA315#v=onepage&q&f=false page 315].</ref><ref>See, for example: Martin Eden Glicksman, ''Principles of Solidification'', (New York, New York: Springer Science + Business Media, 2011), [http://books.google.com/books?id=rXMuZY08KfkC&pg=PA199#v=onepage&q&f=false pages 199-201].</ref> | |||
It should be mentioned that in the literature, there is still not agreement about the specific equation to which the name "Gibbs-Thomson equation" refers. For example, in the case of some authors, it's another name for the "Ostwald-Freundlich equation"<ref>J. G. McLean et al., "A model and simulation of the decay of isolated nanoscale surface features" in: M.C. Tringides, ed., ''Surface Diffusion: Atomistic and collective processes'' (New York, New York: Plenum Press, 1997), [http://books.google.com/books?id=iL0yrWK22-kC&pg=PA378#v=onepage&q&f=false page 378.]</ref> — which, in turn, is often called the "Kelvin equation" — whereas in the case of other authors, the "Gibbs-Thomson relation" is the Gibbs free energy that's required to expand the interface,<ref>M. W. Barsoum, ''Fundamentals of Ceramics'' (New York, New York: Taylor & Francis, 2003), [http://books.google.com/books?id=Q11iM9FXDqQC&pg=PA346#v=onepage&q&f=false page 346].</ref> and so forth. | |||
== References == | |||
<!--- See http://en.wikipedia.org/wiki/Wikipedia:Footnotes on how to create references using <ref></ref> tags which will then appear here automatically --> | |||
{{Reflist}} | |||
{{DEFAULTSORT:Gibbs-Thomson equation}} | |||
[[Category:Thermodynamic equations]] |
Latest revision as of 19:06, 13 June 2013
- The Gibbs–Thomson Effect, in common physics usage, refers to variations in vapor pressure or chemical potential across a curved surface or interface. The existence of a positive interfacial energy will increase the energy required to form small particles with high curvature, and these particles will exhibit an increased vapor pressure. See Ostwald–Freundlich equation.
- More specifically, the Gibbs–Thomson effect refers to the observation that small crystals are in equilibrium with their liquid melt at a lower temperature than large crystals. In cases of confined geometry, such as liquids contained within porous media, this leads to a depression in the freezing point / melting point that is inversely proportional to the pore size, as given by the Gibbs–Thomson equation.
Introduction
- The technique is closely related to using gas adsorption to measure pore sizes, but uses the Gibbs–Thomson equation rather than the Kelvin equation. They are both particular cases of the Gibbs Equations of Josiah Willard Gibbs: the Kelvin equation is the constant temperature case, and the Gibbs–Thomson equation is the constant pressure case.[1]
- This behaviour is closely related to the capillary effect and both are due to the change in bulk free energy caused by the curvature of an interfacial surface under tension.[2][3]
- The original equation only applies to isolated particles, but with the addition of surface interaction terms (usually expressed in terms of the contact wetting angle) can be modified to apply to liquids and their crystals in porous media. As such it has given rise to various related techniques for measuring pore size distributions, see Themoporometry and Cryoporometry.
- The Gibbs–Thomson effect lowers both melting and freezing point, and also raises boiling point. However, simple cooling of an all-liquid sample usually leads to a state of non-equilibrium super cooling and only eventual non-equilibrium freezing. To obtain a measurement of the equilibrium freezing event, it is necessary to first cool enough to freeze a sample with excess liquid outside the pores, then warm the sample until the liquid in the pores is all melted, but the bulk material is still frozen. Then, on re-cooling the equilibrium freezing event can be measured, as the external ice will then grow into the pores.[4][5]
This is in effect an "ice intrusion" measurement (cf. Mercury Intrusion), and as such in part may provide information on pore throat properties. The melting event can be expected to provide more accurate information on the pore body.
Gibbs–Thomson equation for particles
- For an isolated spherical solid particle of diameter in its own liquid, the Gibbs-Thomson Equation for the structural melting point depression can be written:[6]
- Where:
- TmB=Bulk Melting temperature
- σsl = solid–liquid interface energy (per unit area)
- Hf = bulk enthalpy of fusion (per gram of material)
- ρs = density of solid
The "4" in the above equation comes from the spherical geometry of the solid-liquid interface.
Note: is used for the pore size rather than for a number of reasons :
- It is consistent with the original published notation.
- The equation can be used with planar geometry (with a change of constant).
- For consistency with the related Strange–Rahman–Smith equation where the symbol is used for the differential operator.
Gibbs–Thomson equation for liquids in pores
Very similar equations may be applied to the growth and melting of crystals in the confined geometry of porous systems. However the geometry term for the crystal-liquid interface may be different, and there may be additional surface energy terms to consider, which can be written as a wetting angle term . The angle is usually considered to be near 180°. In cylindrical pores there is some evidence that the freezing interface may be spherical, while the melting interface may be cylindrical, based on preliminary measurements for the measured ratio for in cylindrical pores.[7]
Thus for a spherical interface between a non-wetting crystal and its own liquid, in an infinite cylindrical pore of diameter , the structural melting point depression is given by:[8]
Simplified Gibbs-Thomson equation
The Gibbs–Thomson equation may be written in a compact form:[9]
where the Gibbs-Thomson Coefficient assumes different values for different liquids[6][7] and different interfacial geometries (spherical/cylindrical/planar).[7]
Where : is a geometric constant dependent on the interfacial shape,
History
By 1906, the German physical chemist Friedrich Wilhelm Küster (1861-1917) had predicted that since the vapor pressure of a finely pulverized volatile solid is greater than the vapor pressure of the bulk solid, then the melting point of the fine powder should be lower than that of the bulk solid.[11] Investigators such as the Russian physical chemist Pavel Nikolaevich Pavlov (1872-1953) searched for and eventually observed such melting point depression. They recognized that the depression occurred when the change in surface energy was significant compared to the latent heat of the phase transition, which condition obtained in the case of very small particles.[12]
Neither Josiah Willard Gibbs nor William Thomson (Lord Kelvin) derived the Gibbs–Thomson equation.[13] Also, although many sources claim that British physicist J. J. Thomson derived the Gibbs–Thomson equation in 1888, he did not.[14] Early in the 20th century, investigators derived precursors of the Gibbs–Thomson equation.[15] However, in 1920, the Gibbs-Thomson equation was first derived in its modern form by two researchers working independently: Friedrich Meissner, a student of the Estonian-German physical chemist Gustav Tammann, and Ernst Rie (1896-1921), an Austrian physicist at the University of Vienna.[16][17] These early investigators did not call the relation the "Gibbs-Thomson" equation. That name was in use by 1910 or earlier;[18] it originally referred to equations concerning the adsorption of solutes by interfaces between two phases — equations that Gibbs and then J. J. Thomson derived.[19] Hence, in the name "Gibbs-Thomson" equation, "Thomson" refers to J. J. Thomson, not William Thomson (Lord Kelvin).
In 1871, William Thomson published an equation describing capillary action and relating the curvature of a liquid-vapor interface to the vapor pressure:[20]
where
- = vapor pressure at a curved interface of radius
- = vapor pressure at a flat interface () =
- = surface tension
- = density of vapor
- = density of liquid
- , = radii of curvature along the principal sections of the curved interface.
In his dissertation of 1885, Robert von Helmholtz (son of German physicist Hermann von Helmholtz) showed how the Ostwald-Freundlich equation
could be derived from Kelvin's equation.[21][22] The Gibbs–Thomson equation can then be derived from the Ostwald-Freundlich equation via a simple substitution using the integrated form of the Clausius-Clapeyron relation:[23]
The Gibbs–Thomson equation can also be derived directly from Gibbs' equation for the energy of an interface between phases.[24][25]
It should be mentioned that in the literature, there is still not agreement about the specific equation to which the name "Gibbs-Thomson equation" refers. For example, in the case of some authors, it's another name for the "Ostwald-Freundlich equation"[26] — which, in turn, is often called the "Kelvin equation" — whereas in the case of other authors, the "Gibbs-Thomson relation" is the Gibbs free energy that's required to expand the interface,[27] and so forth.
References
43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.
- ↑ 1.0 1.1 One of the biggest reasons investing in a Singapore new launch is an effective things is as a result of it is doable to be lent massive quantities of money at very low interest rates that you should utilize to purchase it. Then, if property values continue to go up, then you'll get a really high return on funding (ROI). Simply make sure you purchase one of the higher properties, reminiscent of the ones at Fernvale the Riverbank or any Singapore landed property Get Earnings by means of Renting
In its statement, the singapore property listing - website link, government claimed that the majority citizens buying their first residence won't be hurt by the new measures. Some concessions can even be prolonged to chose teams of consumers, similar to married couples with a minimum of one Singaporean partner who are purchasing their second property so long as they intend to promote their first residential property. Lower the LTV limit on housing loans granted by monetary establishments regulated by MAS from 70% to 60% for property purchasers who are individuals with a number of outstanding housing loans on the time of the brand new housing purchase. Singapore Property Measures - 30 August 2010 The most popular seek for the number of bedrooms in Singapore is 4, followed by 2 and three. Lush Acres EC @ Sengkang
Discover out more about real estate funding in the area, together with info on international funding incentives and property possession. Many Singaporeans have been investing in property across the causeway in recent years, attracted by comparatively low prices. However, those who need to exit their investments quickly are likely to face significant challenges when trying to sell their property – and could finally be stuck with a property they can't sell. Career improvement programmes, in-house valuation, auctions and administrative help, venture advertising and marketing, skilled talks and traisning are continuously planned for the sales associates to help them obtain better outcomes for his or her shoppers while at Knight Frank Singapore. No change Present Rules
Extending the tax exemption would help. The exemption, which may be as a lot as $2 million per family, covers individuals who negotiate a principal reduction on their existing mortgage, sell their house short (i.e., for lower than the excellent loans), or take part in a foreclosure course of. An extension of theexemption would seem like a common-sense means to assist stabilize the housing market, but the political turmoil around the fiscal-cliff negotiations means widespread sense could not win out. Home Minority Chief Nancy Pelosi (D-Calif.) believes that the mortgage relief provision will be on the table during the grand-cut price talks, in response to communications director Nadeam Elshami. Buying or promoting of blue mild bulbs is unlawful.
A vendor's stamp duty has been launched on industrial property for the primary time, at rates ranging from 5 per cent to 15 per cent. The Authorities might be trying to reassure the market that they aren't in opposition to foreigners and PRs investing in Singapore's property market. They imposed these measures because of extenuating components available in the market." The sale of new dual-key EC models will even be restricted to multi-generational households only. The models have two separate entrances, permitting grandparents, for example, to dwell separately. The vendor's stamp obligation takes effect right this moment and applies to industrial property and plots which might be offered inside three years of the date of buy. JLL named Best Performing Property Brand for second year running
The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more
There are various methods to go about discovering the precise property. Some local newspapers (together with the Straits Instances ) have categorised property sections and many local property brokers have websites. Now there are some specifics to consider when buying a 'new launch' rental. Intended use of the unit Every sale begins with 10 p.c low cost for finish of season sale; changes to 20 % discount storewide; follows by additional reduction of fiftyand ends with last discount of 70 % or extra. Typically there is even a warehouse sale or transferring out sale with huge mark-down of costs for stock clearance. Deborah Regulation from Expat Realtor shares her property market update, plus prime rental residences and houses at the moment available to lease Esparina EC @ Sengkang - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ 6.0 6.1 Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ 7.0 7.1 7.2 Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ The geometry of the crystal–liquid interface determines the value of the constant in the Gibbs–Thomson equation – the conventional "4" only applies to a spherical interface in a cylindrical pore.
- ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ Friedrich Wilhelm Küster (1906) Lehrbuch der allgemeinen physikalischen und theoretischen Chemie … [Textbook of general physical and theoretical chemistry … ] (Heidelberg, Germany: Carl Winter, 1906), v.1, p. 189. The relevant passage is reprinted on page 189 of volume 1 of the 1913 edition: § 127. Schmelzen feinster Pulver. (Melting of the finest powder). From page 189: "Folglich ist die Schmelztemperatur des Pulvers, t1°, niedriger als die der Kristalle, t°. Der Unterschied ist jedoch so gering, daß er noch nicht zur Beobachtung gelangt ist (vgl. weiter unter §. 131)." (Consequently, the melting temperature of the powder, t1°, is lower than that of the [bulk] crystal, t°. However, the difference is so small that it still hasn't been observed (compare §. 131 below).)
- ↑ See, for example:
- Pawlow, P. N. (1909) "Über die Abhängigkeit des Schmelzpunktes von der Oberflächenenergie eines festen Korpers" (On the dependency of the melting point on the surface energy of a solid body), Zeitschrift für physikalische Chemie, 65 : 1-35 ; 545-548.
- Pawlow, P. N. (1910) "Ueber den Einfluss der Oberfläche einer festen Phase auf die latente Wärme und die Temperatur des Schmelzens" (On the effect of the surface of a solid phase on the latent heat and the temperature of melting), Zeitschrift für Chemie und Industrie der Kolloide, 7 : 37-39.
- ↑ Jeong-Myeong Ha, Crystallization and Thermotropic Properties of Organic Solids in Nanoscopic Reactors, Ph.D. thesis: University of Minnesota, 2006, pages 26-28.
- ↑ Sir Joseph John Thomson derived Kelvin's equation (page 163) and the depression of the melting point of ice by pressure (page 258), but he did not derive the Gibbs-Thomson equation. However, on pages 251-252, Thomson considered the effects of temperature and surface tension on the solubility of salts in spherical droplets, and he obtained an equation for that phenomenon which has a form similar to that of the Gibbs-Thomson equation. See: Thomson, J.J., Applications of dynamics to physics and chemistry (London, England: Macmillan and Co., 1888).
- ↑ See:
- Pawlow, P. N. (1909) "Über die Abhängigkeit des Schmelzpunktes von der Oberflächenenergie eines festen Korpers" (On the dependency of the melting point on the surface energy of a solid body), Zeitschrift für physikalische Chemie, 65 : 545-548. [Note: "P. N. Pawlow" was a Russian physical chemist, Pavel Nikolaevich Pavlov (1872-1953).]
- Tammann, Gustav H.J.A. (1920) "Über eine Methode zur Bestimmung der Abhängigkeit des Schmelzpunktes einer Kristallamelle von ihrer Dicke" (On a method for the determination of the dependency of the melting point of a crystal plate on its thickness), Zeitschrift für anorganische und allgemeine Chemie, 110 (1) : 166-168.
- ↑ Meissner, F. (1920) "Mitteilungen aus dem Institut für physikalische Chemie der Universität Göttingen. Nr. 8. Über den Einfluß der Zerteilung auf die Schmelztemperatur" (Communications from the Institute for Physical Chemistry of the University of Göttingen. Nr. 8. On the influence of division on the melting point), Zeitschrift für anorganische und allgemeine Chemie, 110 (1) : 169-186. Meißner presents a form of the Gibbs-Thomson equation as equation (2) on page 174.
- ↑ Note:
- Ernst Rie first published the Gibbs-Thomson equation in 1920 in his dissertation for a degree from the University of Vienna.
- Extracts from that dissertation were published in 1923 in: Ernst Rie (1923) "Über die Einfluss der Oberflächenspannung auf Schmelzen und Gefrieren" (On the influence of surface tension on melting and freezing), Zeitschrift für physikalische Chemie, 104 : 354-362.
- A draft version of Rie's article in the Zeitschrift für physikalische Chemie appeared in: Ernst Rie (1920) Vorläufige Meitteilung: "Einfluß der Oberflächenspannung auf Schmelzen und Gefrieren" (Preliminary notice: Influence of surface tension on melting and freezing), Anzeiger der Akademie der Wissenschaften in Wien: Mathematisch-naturwissenschaftliche Klasse (Gazette of the Philosophical Academy of Vienna: mathematical-scientific section), 57 : 137-139. Available on-line at: State Museum of Austria. The Gibbs-Thomson equation appears on page 138.
- ↑ See, for example:
- A.B. Macallum (October 7, 1910) "Surface tension in relation to cellular processes," Science, 32 (823) : 449-458. After explaining the Gibbs-Thomson principle (and its origin) on page 455, he uses the term "Gibbs-Thomson principle" on page 457: "This determination is based on the deduction from the Gibbs-Thomson principle that, where in a cell an inorganic element or compound is concentrated, the surface tension at the point is lower than it is elsewhere in the cell."
- See also: A.B. Macallum (October 14, 1910) "Surface tension in relation to cellular processes. II," Science, 32 (824) : 492-502.
- Duncan A. MacInnes and Leon Adler (1919) "Hydrogen overvoltage," Journal of the American Chemical Society, 41 (2) : 194-207. "By the Gibbs-Thompson law, substances that lower the surface tension are those which are adsorbed."
- Shanti Swarup Bhatnagar and Dasharath Lal Shrivastava (1924) "The optical inactivity of the active sugars in the adsorbed state -- a contribution to the chemical theory of adsorption. I," Journal of Physical Chemistry, 28 (7) : 730-743. From page 730: "There are at present three well-known theories regarding the mechanism of protective action of colloids: (1) That the protecting agent concentrates at the interface of the colloid particles and the dispersion medium according to [the] Gibbs-Thomson law, …"
- Ashutosh Ganguli (1930) "On the adsorption of gases by solids," Journal of Physical Chemistry, 34 (3) : 665-668. From page 665: "The intimate connection of adsorption with surface tension was shown long before by Gibbs, subsequently known as the Gibbs-Thomson equation."
- ↑ Frederick George Donnan and Arthur Erich Haas, ed.s, A Commentary on the Scientific Writings of J. Willard Gibbs, vol. 1 (New Haven, Connecticut: Yale University Press, 1936), page 544. In 1878, Gibbs published an equation concerning the adsorption of a solute by an interface between two phases, and in 1888, J.J. Thomson published an equation concerning the same phenomenon, which he'd derived via a different method but which superficially resembled Gibbs' result. Apparently both equations were eventually known as "the Gibbs-Thomson equation". From page 544: "There is a rather prevalent impression that the two equations are the same, but that is not so; and both on grounds of priority and because of the wider scope of Gibbs' result, there is no justification for the use of the name "Gibbs-Thomson equation" which one sometimes meets in the literature, although it is doubtless true that Thomson's work was independently carried out."
- ↑ Sir William Thomson (1871) "On the equilibrium of vapour at a curved surface of liquid," Philosophical Magazine, series 4, 42 (282) : 448-452. See equation (2) on page 450.
- ↑ Robert von Helmholtz (1886) "Untersuchungen über Dämpfe und Nebel, besonders über solche von Lösungen" (Investigations of vapors and mists, especially of such things from solutions), Annalen der Physik, 263 (4) : 508-543. On pages 523-525, Robert von Helmholtz converts Kelvin's equation to the Ostwald-Freundlich equation.
- ↑ Robert von Helmholtz’s derivation of the Ostwald-Freundlich equation from Kelvin’s equation is reproduced (in English) on the "Talk" page of Wikipedia's article on the Ostwald-Freundlich equation.
- ↑ This derivation of the Gibbs-Thomson equation appears on pages 417-418 of: James E. McDonald (December 1953) "Homogeneous nucleation of supercooled water drops," Journal of Meteorology, 10 : 416-433. Available on-line at: Princeton.edu
- ↑ Josiah Willard Gibbs (1878) "On the equilibrium of heterogeneous substances," Transactions of the Connecticut Academy of Arts and Sciences, 3 : 343-524. The equation for the energy that's required to create a surface between two phases appears on page 483. Reprinted in: Josiah Willard Gibbs with Henry Andrews Bumstead and Ralph Gibbs van Name, ed.s, The Scientific Papers of J. Willard Gibbs, …, vol. 1, (New York, New York: Longmans, Green and Co., 1906), page 315.
- ↑ See, for example: Martin Eden Glicksman, Principles of Solidification, (New York, New York: Springer Science + Business Media, 2011), pages 199-201.
- ↑ J. G. McLean et al., "A model and simulation of the decay of isolated nanoscale surface features" in: M.C. Tringides, ed., Surface Diffusion: Atomistic and collective processes (New York, New York: Plenum Press, 1997), page 378.
- ↑ M. W. Barsoum, Fundamentals of Ceramics (New York, New York: Taylor & Francis, 2003), page 346.