[TheForge] plastic forge? OT:

[Jerry Frost]

LCDs Pete?

Jer
----- Original Message ----- 
From: "peter fels" <artgawk at thegrid.net>
To: "Blacksmithing List Sponsored by ABANA" <theforge at mailman.qth.net>
Sent: Thursday, June 16, 2011 5:58 PM
Subject: Re: [TheForge] plastic forge? OT:


>
> On Jun 16, 2011, at 9:48 AM, Bruce Freeman wrote:
>
>> Free electrons are involved in the absorption of light due to the fact
>> that a photon of light will "promote" an electron from a lower- to a
>> higher-energy state.  In pure elements, this is what gives rise to the
>> absorbance spectra of the element (hydrogen, for example).  It is also
>> the case for molecules.  The more possible energy states available for
>> an electron to "reside" in, the more different possible transitions
>> possible.  A photon of a particular energy corresponds to a 'color'.
>
> Got it...thanks!
>>
>> I don't see how running a current through a transparent material would
>> have anything to do with color.  Salt water conducting electricity
>> remains clear, but then electrons don't run through salt water -- ions
>> do.  I would suppose it unusual for a transparent material to be able
>> to conduct electricity.  Can you think of one?
>
> Nope...other that possibly graphene ( but i may remember that wrong).
> Thought there was some work on using it for monitor display screens.
>>
>> On Thu, Jun 16, 2011 at 12:38 PM, peter fels <artgawk at thegrid.net> wrote:
>>>
>>>>
>>>>
>>>>
>>>> As you probably know, diamond is crystalline carbon, in which each
>>>> atom is connected to four others in a tetrahedral configuration (i.e.,
>>>> the OTHER four carbons are at the corners of a tetrahedron).  Very
>>>> strong, very hard, no free electrons so completely transparent.
>>>>
>>>> By contrast, graphite is crystalline carbon, in which each atom is
>>>> connected to only three others in a hexagonal array (i.e., honeycomb
>>>> or chickenwire shape).  This is even stronger than diamond within the
>>>> plane.  However, the myriad of layers of carbon are only held together
>>>> by their electronic interaction and whatever stuff that attracts to
>>>> between the planes.  There are LOTS of loose electrons floating
>>>> around, so virtually any wavelength of visible light can be absorbed,
>>>> rendering the stuff black.
>>>>
>>>>>>> How fascinating.
>>> Bruce, do you know why free electrons absorb light?
>>> Does this mean that running a small current through or across a 
>>> transparent  material will male it opaque?
>>>>>>>