lotto@wjh12.HARVARD.EDU (Jerry Lotto) (10/15/86)
In article <666@faron.UUCP> jp@faron.UUCP (Jeffrey Picciotto) writes: >Actually glass is a fluid (though not a liquid). The issue (in the case >of glass) is wether or not it is crystalline. It is not. Being in a >"rigid condition" does not preclude being a fluid. Does that mean that a (non-crystalline) polymer at a temp. beneath the Tg is a fluid as well? I have not seen a definition that I have been happy with, but all that I do see imply that a fluid is a state of matter that is not rigid. I have always used the term "glass" to describe various materials that are non-crystalline, non-particulate solids, but this is more of a practical matter for a synthetic chemist.
jmc@riccb.UUCP (Jeff McQuinn ) (10/17/86)
> Actually glass is a fluid (though not a liquid). The issue (in the case > of glass) is wether or not it is crystalline. It is not. Being in a > "rigid condition" does not preclude being a fluid. > > --jeff I read somewhere a long time ago that measurements taken on very old cathedral windows proves that the glass in them actually flows. The windows are many centuries old and are now several inches thicker on the bottom then on the top. I've often wished I could visit a medevial church just to see this phenomenon. Jeff McQuinn just VAXing around
berleant@ut-sally.UUCP (Dan Berleant) (10/25/86)
While Mercury, glass, freon, carbon tetrachloride, and my leftover coffee are good first approximations to liquids with no hydrogen, don't bet your silly putty on it! If gasoline contains hydrogen (when in fact it doesn't -- it contains an assortment of octane and other hydrocarbon molecules) then glass is full of hydrogen. Silicon nuclei are made of the stuff. Everything normal is. So there is no H-less liquid anywhere on earth (except maybe that coffee). Is there any H-less liquid anywhere? Are neutron stars made of H-less liquid? Beats me!
zdenek@heathcliff.columbia.edu (Zdenek Radouch) (10/26/86)
In article <6091@ut-sally.UUCP> berleant@ut-sally.UUCP (Dan Berleant) writes: > > If gasoline contains hydrogen (when in fact it doesn't -- it > contains an assortment of octane and other hydrocarbon molecules) > then glass is full of hydrogen. Silicon nuclei are made of > the stuff. Everything normal is. So there is no H-less > liquid anywhere on earth (except maybe that coffee). Dan, that's not bad! But don't forget about your audience. Alchemist hopes, that he can turn lead into gold. Chemist knows, that it's not possible. Physicist knows, that it's difficult. God knows how to do it. zdenek ------------------------------------------------------------------------- Men are four: He who knows and knows that he knows, he is wise - follow him; He who knows and knows not that he knows, he is asleep - wake him; He who knows not and knows that he knows not, he is simple - teach him; He who knows not and knows not that he knows not, he is a fool - shun him! zdenek@CS.COLUMBIA.EDU or ...!seismo!columbia!cs!zdenek Zdenek Radouch, 457 Computer Science, Columbia University, 500 West 120th St., New York, NY 10027
mikes@tekecs.TEK.COM (Michael Sellers) (10/27/86)
In article <6091@ut-sally.UUCP>, berleant@ut-sally.UUCP (Dan Berleant) writes: > [...] > If gasoline contains hydrogen (when in fact it doesn't -- it > contains an assortment of octane and other hydrocarbon molecules) Could you *please* explain this? Is this humor and its just too late at night for me, or are you serious? Gasoline contains many many hydrogen atoms covalently bonded to carbons in chains ranging from 1 carbon to 8 or 10 carbons in length. "Octane" by definition is a molecule containing a chain of 8 carbons, all singly bonded together, and, in the absence of any other qualifiers, containing 18 hydrogen atoms. "Hydrocarbons" by definition are molecules made up of --you guessed it-- HYDROgen and CARBON. > then glass is full of hydrogen. Silicon nuclei are made of > the stuff. Everything normal is. So there is no H-less > liquid anywhere on earth (except maybe that coffee). Are you trying to equate hydrogen atoms with protons? They aren't the same (except in extreme cases). Even in hydroflouric acid (HF), the hydrogen atom retains some if the electron cloud, making it not quite a bare proton. And, short of using a very powerful cyclotron (and maybe even then), I'd like to see you generate Hydrogen from Silicon. *That* would be a neat trick. -- Mike Sellers UUCP: {...your spinal column here...}!tektronix!tekecs!mikes "The goal of AI is not yet insight."
eberline@cory.Berkeley.EDU ( ) (10/28/86)
In article <752@riccb.UUCP> jmc@riccb.UUCP (Jeff McQuinn ) writes: >I read somewhere a long time ago that measurements taken on very old cathedral >windows proves that the glass in them actually flows. The windows are many >centuries old and are now several inches thicker on the bottom then on the >top. I've often wished I could visit a medevial church just to see this >phenomenon. My old physics prof wrote this off as being a result of the unsophisticated glassworking methods of the time. (On the other hand, this was the same guy who delivered the classic "Baby in a Box" lecture on entropy in a closed system.) eberline@cory.Berkeley.EDU.UUCP