[mythtv-users] OT: Nokia N800 only $236 at Amazon
R. G. Newbury
newbury at mandamus.org
Wed Oct 31 13:42:51 UTC 2007
David Brodbeck wrote:
> On Oct 31, 2007, at 4:57 AM, R. G. Newbury wrote:
>> IIRC Nikon stopped producing Ti bodies because of environmental
>> about steps in the production process...They were producing some toxic
>> by-product from a cleaning process (priopr to anodization iirc). The
>> acid wash produced titanium dioxide (the white in white paint), and
>> was being dumped/escaped/poisoning the workers/offending the
>> greens...and Japan is more than a little wary of environmental toxins
>> (can you spell 'mercury poisoning'?).
> Hmm. Sure it was titanium dioxide? It's pretty inert and non-
> toxic. It's even used as a white coloring in some foods. There's
> some evidence it can cause lung cancer if you inhale a lot of it as
> dust, though.
> There were, at some points in history, availability problems with
> titanium. Most of the large titanium ore deposits are located in the
> former Soviet Union. There are stories that, during the cold war,
> the U.S. military was unable to procure it in sufficient quantities
> to make military aircraft, and resorted to buying many gallons of
> white paint in order to extract the titanium dioxide.
Hmmm, maybe it was the oxide or tri-oxide or even the acids which
were needed... I cannot remember. I do remember reading something about
pollution from titanium effluent from a paint factory in the St.
Lawrence River near Trois Riviere affecting beluga whales...(They're
already wwhite! How could we tell?)
The real reason may well have been that machining a titanium blank was
just too damned expensive and they could not sell the Ti ones for a
sufficient price premium... Bad enough when you are selling an expensive
product to start with, that you are making one which has double the
working life of your standard unit!
Stories...Just that. Buying white paint for the dioxide...Hah. Titanium
is reasonably well distributed worldwide although in small quantities.
It is extremely hard to deal with and refine. It's been far too many
years since I earned the Geology degree on my office wall, but some of
that stuck to my neurons...(uhhh neutrons before coffee in the morning!)
And I have real doubts are to the efficiency of making large titanium
billets from the small amounts in white paint. You would still have to
refine/remelt the TiO2. And that process is difficult and expensive.
Gold melts at about 2000F and titanium at somewhere near 3000F (going
Tux says: "Be regular. Eat cron flakes."
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