Cosmological confusion

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Can anyone provide some cites and some discussion of nucleation in cosmology? Nucleation is a key concept in false vacuum inflation, it would be nice to get some treatment of that. --Keflavich 19:51, 1 April 2006 (UTC)Reply

I was just about to ask a similar question! What about gravitational nucleation? when the universe was finding its feet, it was a uniform cloud, no? What caused it to form nebulae, stars, and planets? - jak (talk) 03:06, 13 June 2006 (UTC)Reply
Fix it. DCDuring 16:41, 24 September 2007 (UTC)Reply

Can you write who discovered nucleation? i need to know for a project. —Preceding unsigned comment added by 72.54.128.137 (talk) 14:11, 1 October 2008 (UTC)Reply

Help Request

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I noticed that this page has an external link to a page about the coke and mentos experience. I created a page about the mentos eruption phenomenon (Mentos eruption). But I'm not a scientist so any help you could provide editing it (especially the scientific explanation section) would be great. I'm sure that you would do much better at it than me. (Toritaiyo 17:39, 7 August 2006 (UTC))Reply

Heterogeneous nucleation form factor

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I get a different result for the form factor relating the free energy for heterogeneous nucleation as a proportion of the free energy of homogeneous nucleation. Can anyone add a source to confirm?

 

Grunkhead (talk) 14:25, 11 April 2010 (UTC)Reply


This rate is valid only if the heterogeneous nucleation takes place on a plane surface. In other cases the "geometric factor" has more complicated form. You can check any of text books for nucleation for further reference. —Preceding unsigned comment added by 128.252.20.193 (talk) 21:20, 28 June 2010 (UTC)Reply

The original expression in the page was right, but as note above applies only to the (unrealistic) case of a perfectly smooth surface, so I have replaced the equation with a qualitative discussion of the effect of contact angle and surface geometry on nucleation. rpsear 26th Dec 2013 — Preceding unsigned comment added by Rpsear (talkcontribs) 19:35, 26 December 2013 (UTC)Reply

Ambiguity regarding the example of chemical nucleation

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"Most nucleation processes are physical, rather than chemical, but a few exceptions do exist (e.g. electrochemical nucleation) . A good example would be the famous Diet Coke and Mentos eruption". First of all, is electrochemical nucleation the only exception, the only form of chemical nucleation, or there are more? If it is the only one, then it's supposed to be "i.e." ("id est", "that is"), not "e.g." (example gratia). Secondly, is the diet(?)-coke-and-menthos case a sort of electrochemical nucleation, or is it just other sort of chemical nucleation, but not electrochemical? --Extremophile (talk) 02:54, 21 April 2010 (UTC)Reply

free energy vs radius graph jpg needs redrawing.

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The interfacial energy + the volume free energy should add up to give the free energy of the system (line in the middle). I understand that it's a sketch but you can see clearly that this line is in the wrong place and therefore may cause confusion. —Preceding unsigned comment added by 82.4.86.255 (talk) 00:46, 14 November 2010 (UTC)Reply

Fixed. I did an improved figure (PNG format) and the page now uses this image - Richard Sear (rpsear) 9th Jan 2014 — Preceding unsigned comment added by Rpsear (talkcontribs) 18:22, 9 January 2014 (UTC)Reply

Modern Theory equation documentation error?

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Is "ΔG" vs "Δs" in this example correct from gibbs free energy equation? Can one substitute "s" here? This does not look correct.

 

Where:

Sativarg (talk) 18:08, 29 June 2011 (UTC)Reply

Sodium acetate nucleation with snapping disk

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The snap disk in warming packs apparently nucleates solidification by exposing microcrystals in small cracks in the metal surface, according to Rogerson, Mansel A, and Silvana S. S Cardoso. 2003. Solidification in heat packs: III. Metallic trigger. AIChE Journal 49(2):522-529. This is according to the abstract, I don't have access to the full paper. This should also be clarified in the article sodium acetate. Robert Hiller (talk) 06:42, 8 March 2012 (UTC)Reply

Another citation along those same lines is B. Sandnes, The physics and the chemistry of the heat pad, Am. J. Phys. 76, 546 (2008); http://dx.doi.org/10.1119/1.2830533 Dder (talk) 14:22, 16 November 2014 (UTC)Reply