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September 29th, 2018, 07:48 PM   #11
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Titration - analysis of an indigestion tablet - studylib.net
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September 30th, 2018, 01:43 AM   #12
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It's a surface tension effect from either drying or cooling or both.
Such a pattern is very common in Nature as it is a minimum energy configuration.

Leave the pancakes out for about 5 million years and they will fossilize to a miniature Giant's Causeway.

The pattern is also seen in drying mudflats, inadequately irrigated drying concrete and so on.
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September 30th, 2018, 03:18 AM   #13
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Quote:
Originally Posted by Joppy View Post
I wouldn't say very hot. Just enough to melt butter.
Both the butter and the pancake mix contain water, some of which forms steam, especially where the pan is hottest. The steam may be able to push the mixture into a roughly hexagonal pattern, depending on how rapidly the mixture cooks.

Regarding the nature of the pancakes, adequate ingredients are flour, egg, milk and a pinch of salt, so why buy a powder that you mix with water? The mixture doesn't have much flavour of its own, which is possibly one reason why many people fry it in melted butter. However, pancakes cook best in a pan that is initially quite hot, and butter can easily become overheated.
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September 30th, 2018, 05:09 AM   #14
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Quote:
Originally Posted by skipjack View Post
Both the butter and the pancake mix contain water, some of which forms steam, especially where the pan is hottest. The steam may be able to push the mixture into a roughly hexagonal pattern, depending on how rapidly the mixture cooks.

Regarding the nature of the pancakes, adequate ingredients are flour, egg, milk and a pinch of salt, so why buy a powder that you mix with water? The mixture doesn't have much flavour of its own, which is possibly one reason why many people fry it in melted butter. However, pancakes cook best in a pan that is initially quite hot, and butter can easily become overheated.
So you're a cook too!

Look, my mother would kill me if she knew I bought premixed pancake powder. I nearly killed myself from eating it too. I've never used butter for flavour, it's just that I associate oil with savory foods. Also, the pan wouldn't have been hot for the first pancake, but certainly by the second it would have.

I think many factors that allow for the shapes to appear have been mentioned, but nothing has been much more specific than SDK's first response. Studiot's point that the pattern emerges due to it being a minimal energy configuration seems to answer the why but not so much on the how specifically.

I mentioned vibrating membranes in the OP because in that situation the eigenvalues of the solution correspond to the nodal lines ( if i remember correctly..). I was thinking that in an ideal case, such as the equations suggested by SDK, we may have some property of the solution which points specifically to the resulting shape, that's all.
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September 30th, 2018, 05:59 AM   #15
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Instead of butter or oil, one can use a very small amount of pork fat or goose fat. Reduce the heating to a low level just before adding the mixture (with a ladle as a precaution). The rapid initial cooking gives the outside of the pancakes a very slight crispiness and, in my opinion, improves their taste.
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October 1st, 2018, 07:24 AM   #16
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Imagine a large mudflat of perfectly uniform consistency. Evaporation begins at one spot and turns it into a tiny dried spot. The boundary between wet and dry favors further evaporation equally in any direction and the dried area extends in a circle. Eventually the mud flat dries into a continuous solid of smaller size, ie, the whole mud flat shrinks uniformly. The same thing happens when you create a single crystal out of pure molten material and a "seed" to start crystallization.

Now imagine, due to non-homogeneity, a lot of points start evaporating at once creating expanding circles all over the mud flat. Eventually expanding circles meet and the contacts between circles flattens out and the little triangle at the corner becomes a 120 deg triad. Draw three tangent circles and imagine what happens as you push them together. The contact between them flattens and the little triangle in the corner fills in to become a 120deg triad, ie, the corners of a hexagon.

If the density of dry is greater than the density of wet, the contacts crack as the circles come together. It's like a very narrow rivulet of mud between fixed walls. It tries to shrink to a narrower width but is restrained by the walls and so it cracks.

The non-uniform pancake batter is the same thing, except that the dried (cooked) batter expands and as the expanding circles come into contact they form hexagons and push up the thin boundaries of uncooked batter between them.

Soap bubbles on a surface form a hexagonal pattern as they come into contact.

If leavening in batter is uniformly distributed, you get thousands of tiny bubbles which you see when you cut it. If you slice a pancake salami style, you should see a hexagonal pattern of little bubbles.

Last edited by skipjack; October 1st, 2018 at 08:18 AM.
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October 1st, 2018, 08:59 AM   #17
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Hey Zylo, is that taught in all New Jersey High Schools?
In "introduction to hexagons"?
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October 1st, 2018, 09:16 AM   #18
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Quote:
Originally Posted by Denis View Post
Hey Zylo, is that taught in all New Jersey High Schools?
In "introduction to hexagons"?
Irrelevant and insulting comment.

EDIT:
Google "hexagonal packing of circles." Hopefully your High School covers it by the time you become a senior.

Last edited by zylo; October 1st, 2018 at 09:32 AM.
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October 1st, 2018, 09:45 AM   #19
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Geeshhhh...justa tryin' to joke...
A thousand apologies of which you may have one !
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October 1st, 2018, 10:52 AM   #20
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You have a row of discs (circles). Try stacking a second row directly on top of the first. You can't do it. It's an unstable configuration. Each disk in second row drops into the valley created by neighboring disks in the first row. The only stable, and densest, packing is hexagonal. Hexagonal packing isn't a fluke, it's a law of nature.
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