I reckon you compare it to something going viral on the intertubes -
most posts or videos do nothing, they only go viral if enough people
share them.
On 05/01/2017 07:56, Tim Gruene wrote:
> Dear Nicolas,
>
> are you sure this concept is correct?
>
> The entropy of molecules arranged in a crystal must be greatly larger than in
> solution. Hence the driving force for crystallisation is actually a drop in
> energy, and I am not sure there is actually a barrier.
>
> I would take the kids to the play ground and let them run around randomly.
> When I blow a wistle they should line up in an orderly manner.
>
> I am sure it will take some time before some sort of order is achieved, for
> the kids could face in various directions, or line up in blocks, or other
> shapes. Once a seed is there, i.e. once e.g. 4-5 kids have created a regular
> block, it will be much easier for the rest to line up (this is consistent with
> Patrick's explanation).
>
> Cheers,
> Tim
>
> On Wednesday 04 January 2017 05:45:50 PM Nicolas FOOS wrote:
>> Dear Evette,
>>
>> If I was is your situation (explaining nucleation and other concept). I
>> will discuss in terms of energy.
>>
>> I mean obtaining the initial nuclei is the "costly" step in terms of
>> energy. To represent that, out the classical curve of energy, I will use
>> a metaphoric representation such as jump over a barrier and run after.
>>
>> With this analogy, it's possible to explain that the first step is
>> difficult and the second more accessible. If the barrier is to high,
>> it's impossible to continue and run. If you don't have any barrier it's
>> easy to run and if you only have a small barrier is not to difficult to
>> jump over and run. But It also allow you to explain that if you
>> facilitate the apparition of the first "surface" thanks to appropriate
>> method (seeding, dust...) you can help the first step (to continue with
>> the barrier story, it like you have ladder to help, or the ability to
>> decrease the size of the barrier.
>>
>> For why the crystal and how, I will maybe use the example of orange
>> pyramid in the food store. Orange are stable together because they have
>> enough contact, because they have relatively homogeneous shape. If you
>> mixed orange with water melon it's difficult to obtain nice pyramid.
>>
>> For crystallization experiment which work, I have no Idea out of the one
>> you already mentioned.
>>
>>
>> Hope this help.
>>
>> Nicolas
>>
>> Nicolas Foos
>> PhD
>> Structural Biology Group
>> European Synchrotron Radiation Facility (E.S.R.F)
>> 71, avenue des Martyrs
>> CS 40220
>> 38043 GRENOBLE Cedex 9
>> +33 (0)6 76 88 14 87
>> +33 (0)4 76 88 45 19
>>
>> On 30/12/2016 11:06, Radisky, Evette S., Ph.D. wrote:
>>> Can anyone point to some especially useful resources to help explain
>>> to kids (pre-chemistry, ~age 10-12) how and why molecules crystallize?
>>> Maybe a good online movie or animation? I am especially needing help
>>> with the concept of nucleation, and why nucleation is slower and then
>>> crystal growth faster once nuclei have formed. I have been
>>> supervising some experiments growing sucrose crystals from
>>> supersaturated solutions, which have worked really well, but I am
>>> having more difficulty in explaining the underlying fundamental
>>> concepts in a way that is understandable to the kids.
>>>
>>> Thanks!
>>> Evette
>>>
>>> Evette Radisky, PhD
>>>
>>> Associate Professor of Cancer Biology
>>>
>>> Mayo Clinic Cancer Center
>>>
>>> Griffin Cancer Research Building
>>>
>>> 4500 San Pablo Road <x-apple-data-detectors://3/0>
>>>
>>> Jacksonville, FL 32224 <x-apple-data-detectors://3/0>
>>>
>>> tel: 904-953-6372 <tel:904-953-6372>
>>>
>>> fax: 904-953-0277 <tel:904-953-0277>
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