Re: Methanol
- From: spintronic <spintronic@xxxxxxxxxxx>
- Date: Wed, 01 Aug 2007 12:40:18 -0700
On 1 Aug, 19:48, "Perplexed in Peoria" <jimmene...@xxxxxxxxxxxxx>
wrote:
"spintronic" <spintro...@xxxxxxxxxxx> wrote in messagenews:1185991910.702996.9510@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
On 31 Jul, 18:23, "Perplexed in Peoria" <jimmene...@xxxxxxxxxxxxx>
wrote:
"spintronic" <spintro...@xxxxxxxxxxx> wrote in messagenews:1185899276.684639.11390@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
On Jul 31, 1:48 am, Bob Casanova <nos...@xxxxxxxx> wrote:
On Mon, 30 Jul 2007 12:41:14 -0700, the following appeared
in talk.origins, posted by spintronic
<spintro...@xxxxxxxxxxx>:
So, in other words.
"No one knows! of a "plausable" process for producing
methanol in prebiotic conditions on earth"!
IIRC one was given.
You'll have to cite.
Perplexed in peoria. Gave the best explanation but started with
"I don't know that it was produced.
Thx. I'm not buying in to the methanol->formamide story, but I continue
to claim that producing pretty good quantities of methanol on the
early Earth would not have been difficult.
What did you find implausible about it?
1) >> I would expect to get some in a Miller-Urey kind of situation
in an atmosphere with water and methane, but not too much hydrogen.
Simulations in 2005 suggest that Earth could have contained
up to 40% hydrogen.
I think that you are misreading the import of those studies. Kasting,
back around 1970 suggested that the hydrogen content of the atmosphere
could never have been above 5-10% or so, because the hydrogen would
escape into space rapidly by a process known as hydrodynamic escape.
The more recent studies showed that the upper limit on hydrogen - the
threshold for hydrodynamic escape - are higher, more like 40%. But even
without hydrodynamic escape, the hydrogen will still escape slowly
How?
Ordinary gravitational escape.
But, gravitational escape is a very very very, small fraction of
hydrogen leaking into space.
(Unless you turn up the temperature a few hundred degrees on earth).
So In essence we can ignore that scenario.
Which still leaves us with an upper bound of 40 % Hydrogen.
Some small fraction of the hydrogen molecules
or hydrogen atoms will have escape velocity.
Very unlikely. & is dependant on temperature!
What distinguishes 'hydrodynamic
escape' from ordinary gravitational escape is that in 'hydrodynamic escape',
you have so much stuff escaping so quickly that it drags everything else along
with it.
and you would need a pretty strong and continuous source of hydrogen to get
the level anywhere near that high. And the new studies did not, IMO,
suggest a plausible source of hydrogen.
Photodissociation of hydrogen from water is the only answer! But that
puts free radicals into the atmosphere, so no amino acids!
Er. The whole mechanism of Miller-Urey is that the uv or the electric
discharge produces free radicals! And, in any case, the radicals produced
in the course of photodissociation of water tend to be at higher altitudes
than the ones involved in Miller-Urey processes. And, in any cases, the
amino acids produced by Miller-Urey don't remain long in the atmosphere to
encounter further free radicals. They are washed out of the atmosphere by
rain into the oceans, where they supposedly accumulate until they reach a
steady-state concentration of 'dilute soup'.
Curious as Half of lifes 20 amino acids have
(NONPOLAR HYDROPHOBIC) R Groups.
Nonpolar (Hydrophobic) R Groups
Glycine (Gly)
Alanine (Ala)
Valine (Val)
Leucine (Leu)
Isoleucine (Ile)
Proline (Pro)
Methionine (Met)
Phenylalanine (Phe)
Tryptophan (Trp)
Thats not a good recipe for an organic soup
Washed out of the atmosphere by
rain into the oceans
So, even with the new studies,
I doubt that the atmospheric hydrogen level was ever higher than 5% or
so after 4 Bya. And probably not that high.
Well you know best, not the universities!
So who do we trust? You, Universities, Common sense????
I'm just curious.
You believe, what you choose to believe.
Only because you knoe the required chemistry, cant occur above that
threshold!
What required chemistry?
To form nucleotides!
You seem to forget - I am skeptical of all aspects
of the 'soup' story. But that doesn't mean that I dismiss it without
bothering to learn the chemistry.
Boreans were noble!
2) >> Or in an atmosphere with carbon monoxide, hydrogen, and water.
Here he is describing Syngas, "The Steam reforming of natural gas".
But "fails" to mention, the actual process.
The process requires carbon containing fuel's such as
methane, ethane, butane, propane, carbon dioxide, nitrogen, helium and
hydrogen sulfide.
And temperatures of 400- 1100 °C, Using metal catalysts!
I'm not sure what nitrogen, helium, and H2S are doing in that list.
Simple. Syngas Is the process you describe. But that requires
preexisting
organic chemistry. Which gives off those molecules.
Your ignorance is becoming amusing.
Explain! That would be amusing.
your trolling is becoming pretty boring.
What bores people, is when their beliefs dont add up, and someone
points it out to them.
Like Dad nagging at you not to take drugs!. It's boring, "yes" but
right!
.
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