HDTenEightyP/NetNews huggingface dataset:
From: nomann@diku.dk (Ole Nomann Thomsen)
Newsgroups: rec.arts.sf.science
Subject: Re: Superconductors
Date: 17 Aug 92 09:21:01 GMT
Organization: Department of Computer Science, U of Copenhagen

rob@watney.eng.ohio-state.edu (Rob Carriere) writes:

>In article <1992Aug12.155104.10111@odin.diku.dk> nomann@diku.dk (Ole Nomann Thomsen) writes:
>>How about storing electricity in closed loops of superconducting wire?
>>You could have a transformer where one coil is such a loop, and then 
>>store/fetch the energy via the other coil.
>>This might be a very effective battery, with short rechargeing(sp?) time,

>(It's recharging.  This is English, the spelling is never what it should
> logically be.  :)
(Ack!)

>>big(?) capacity, and virtually no wear.
>>
>>Questions:
>>  Could this work? (I know oh so little about electric engineering).
>>  How much power is there "room for" in a closed loop of s.c.w.?

>A superconductor is only a superconductor under some conditions.  That the
>temperature has to be right is the most well-known one, but not the only one.
>One of the other limits is current density, which would limit the amount of
>power you can store in a given superconductor loop (of course, you can always
>make the loop bigger and thicker and put it in Texas... :).  What the limit is
>varies from material to material; I don't think it is high enough in any one of
>them to make an effective battery, but I'm hardly a materials expert (ie,
>anyone who knows better, please jump in.)  In addition to power limitations,
>you also have the problem that your battery `leaks' in that you need power to
>keep it cooled.  This pretty much kills the idea for any kind of long term
>storage, unless they find a material that is superconductive at room
>temperature.
tmyoung@mailbox.syr.edu (Thomas M. Young) explained to me via E-mail:

1. The critical current, where superconducting stops, is to low for this to
   work (numbered by the uamps/some-square-area or less (how big *is* Texas?:)).

2. The critical magnet field is large*, so you could store energy in 
   a big magnet instead (many loops of sc wire).  It would have to be big, to
   solve the cooling energy problem, and it would try to tear itself apart.
   This is _dangerous_.

*: > 150 tesla.  100 tesla being as energy-dense as TNT, tmyoung sez.

- Ole (still waiting for room-temp. high-critical-current, sc. material).


-- 
No .sig, since it has been warlorded at least twice (why tempt fate).
Newsgroups: rec.arts.sf.science
Subject: Re: Superconductors, the last word please
From: ecmtwhk@ccu1.aukuni.ac.nz (Thomas Koenig)
Date: Thu, 20 Aug 1992 06:39:59 GMT
Organization: University of Auckland, New Zealand.

janowsky@math.rutgers.edu (Steven Janowsky) writes:

>Would you idiots stop arguing about whether the energy in a
>superconducting coil is electrical or magnetic in nature?  Perhaps you
>recall Maxwell, Einstein et al?

Being a chemical engineer, I'm not particularly familiar with these two
gentlemen, but I know the first law of thermodynamics, and I know
confusion between energy and work when I see it, having experienced that
myself :-)

>Next you'll be arguing over `the photon: wave or particle?'

I dunno, maybe the second law of thermodynamics would be more fun
(anybody's built a perpetuum mobile of the second kind lately?) :-)
-- 
Thomas Koenig, ecmtwhk@ccu1.aukuni.ac.nz, ib09@rz.uni-karlsruhe.de
The joy of engineering is to find a straight line on a double logarithmic
diagram.
From: nomann@diku.dk (Ole Nomann Thomsen)
Newsgroups: rec.arts.sf.science
Subject: Re: Superconductors
Date: 12 Aug 92 15:51:04 GMT
Organization: Department of Computer Science, U of Copenhagen

How about storing electricity in closed loops of superconducting wire?
You could have a transformer where one coil is such a loop, and then 
store/fetch the energy via the other coil.
This might be a very effective battery, with short rechargeing(sp?) time,
big(?) capacity, and virtually no wear.

Questions:
  Could this work? (I know oh so little about electric engineering).
  How much power is there "room for" in a closed loop of s.c.w.?
-- 
No .sig, since it has been warlorded at least twice (why tempt fate).
Newsgroups: rec.arts.sf.science
From: ins450m@aurora.cc.monash.edu.au (T.F. Eccles)
Subject: Re: Superconductors
Organization: Monash University, Melb., Australia.
Date: Fri, 14 Aug 1992 05:59:46 GMT

rob@watney.eng.ohio-state.edu (Rob Carriere) writes:

>In article <1992Aug12.155104.10111@odin.diku.dk> nomann@diku.dk (Ole Nomann Thomsen) writes:
>>How about storing electricity in closed loops of superconducting wire?
>>You could have a transformer where one coil is such a loop, and then 
>>store/fetch the energy via the other coil.
>>This might be a very effective battery, with short rechargeing(sp?) time,

>(It's recharging.  This is English, the spelling is never what it should
> logically be.  :)

>>big(?) capacity, and virtually no wear.
>>
>>Questions:
>>  Could this work? (I know oh so little about electric engineering).
>>  How much power is there "room for" in a closed loop of s.c.w.?

>A superconductor is only a superconductor under some conditions.  That the
>temperature has to be right is the most well-known one, but not the only one.

Isn't there also a maximum magnetic field in which a material is a super-
conductor?  Would this affect the current levels?

Eccles, just an Inorganic chemistry student.
Newsgroups: rec.arts.sf.science
From: gapdrr@gsusgi2.gsu.edu (Daniel R T Rothman)
Subject: Re: Merpeople
Organization: Georgia State University
Date: Mon, 17 Aug 1992 16:09:22 GMT

bjgaed@bb1t.monsanto.com writes:

>In article <1517@lysator.liu.se>, matoh@lysator.liu.se (Mats \hrman) writes:
>> u894793@bruny.cc.utas.edu.au (Timothy D Little) writes:
>> 
>>>However, your original problem would presumably be that gills could
>>>not support a mammal the size of a human, underwater.  (Correct me if
>>>not)
>> 
>> Better would be to look at *fish* with a mass larger than or equal to
>> a human, for exampes sharks. What percentage of a shark's volume is
>> gills? Could you fit that volume into a human neck/ribcage? Would a
>> "human" survive on a shark's metabolic rate?
>> 
>Perhaps the issue is not just size when it comes to metabolism.  Large 
>sharks are certainly very active in the water and can be much larger 
>than humans.  Perhaps the issue is one of intelligence.  Whales and 
>dolphins are probably more "intelligent" (don't ask me to define that) 
>than sharks, and a warm-blooded, while sharks and other large fish are 
>cold-blooded.  Is warm-blooded-type metabolism necessary for the 

I don't believe this is the case. there are well documented instances
of smaller, mammal-like dinosaurs that appear to have come relatively
far along the intelligence ladder before getting squashed.

>evolution of higher brain functions?  
>Is air-breathing a prerequisite 
>for warm-blooded metabolism?  If the answer to both of these is yes, 
>then merpeople will have to be warm-blooded air-breathers.  This, of 
>course, assumes only known biochemistry of metabolism and neural 
>processes.  Are the neural processes of cold-blooded animals 
>qualitatively different from those of warm-blooded animals? 

The neurological processes of all vertebrates are VERY similar. Our
favorite taxonomical specimen is the squid, if that gives you any idea
of how "portable" the processes are..


Newsgroups: rec.arts.sf.science
From: ins450m@aurora.cc.monash.edu.au (T.F. Eccles)
Subject: Re: Human flight.
Keywords: Spon
Organization: Monash University, Melb., Australia.
Date: Fri, 14 Aug 1992 06:04:01 GMT

dani@netcom.com (Dani Zweig) writes:

>ins450m@aurora.cc.monash.edu.au (T.F. Eccles):
>>Um. There was also a book called "Windhaven" I think, I can't
>>remember the author,

>George R.R. Martin and Lisa Tuttle.

>>where humans flew b/w settlements, by dropping off cliffs and gliding. The 
>>only supporting reason that they could do it there and not here, was a lower 
>>gravity

>And steady winds.

>>.....but wouldn't that cause a thinner atmosphere?

>Well, Venus has a lower gravity than Earth...

Ok, go to Venus and take a deep breath. :)
The atmospheric density is also affected by the content....you
can try to swap H2SO4 for N2 if you'd _really_ like, but I've
found that it doesn't help....

:)

Eccles
Newsgroups: rec.arts.sf.science
Subject: Re: Evolution under High Gravity
From: ecmtwhk@ccu1.aukuni.ac.nz (Thomas Koenig)
Date: Mon, 17 Aug 1992 22:37:45 GMT
Organization: University of Auckland, New Zealand.

sks1@Ra.MsState.Edu (Sujay Shaunak) writes:


>  
>   Hello, I am interested in getting the net.consensus (as if there ever
>is one) on the effects of living in a high gravity environment. I have noted
>that in *most* SF (at least the I have read), humanoids who live on high
>gravity worlds (relative to earth gravity anyway) are typically shorter,
>stockier, and stronger.

>   I would think that structural and muscular strength would be increased
>so that the being could survive on the planet (or whatever). I would
>not be so quick on height and stockiness. I would think that since the 
>high-g environment would be natural for the being, that other effects
>would dictate growth patterns (like : Is basketball a planetary sport :).

I think the SF authors have got it right, for once.

For one, muscle force increases with the area. In order to lift
themselves up, the inhabitants of a high-g world have to use more force.
This would mean shorter, thicker limbs (assuming constant mass).

Also, the danger of breaking limbs is greater in higher gravity.
Structural strength increases with the cube of the diameter for a hollow
tube of constant thickness, so thicker, shorter bones would be the
result. The reason, btw, why you can't increase the diameter of tubes
forever should be evident for everyone who has ever crushed a Coke can
underfoot.

I once attended a lecture where the professor demonstrated you can quite
easily calculate the diameter/height ratios of trees from technical
mechanics; you can also do the same for the thickness of bones of us and
our closer relatives, such as goriallas, etc. Unfortunately, I'm about
20000 km from my notes at the moment.

I don't think that greater structural strength would come about as
easily. If it could be done very easily, we would already have it here.
-- 
Thomas Koenig, ecmtwhk@ccu1.aukuni.ac.nz, ib09@rz.uni-karlsruhe.de
The joy of engineering is to find a straight line on a double logarithmic
diagram.
Newsgroups: rec.arts.sf.science
From: rob@volga.eng.ohio-state.edu (Rob Carriere)
Subject: Re: Superconductors, the last word please
Organization: The Ohio State University Dept of Electrical Engineering
Date: Thu, 20 Aug 1992 03:20:59 GMT

In article <Aug.19.10.50.42.1992.13852@math.rutgers.edu>
janowsky@math.rutgers.edu (Steven Janowsky) writes: 
>Would you idiots stop arguing about whether the energy in a
>superconducting coil is electrical or magnetic in nature?  Perhaps you
>recall Maxwell, Einstein et al?

Sorry, I'm too young to have met either of those fine gentlemen.  _You_ may,
however, perhaps recall that the former gentleman's equations contain
electrical and magnetic terms, and further,  that in many situations the
equations decouple in such a fashion that one can meaningfully speak of the
two components as separate fields.  As for Einstein, I don't particularly feel
like chasing relativistic equations through a current loop if I don't have to.
Your milage may vary.

>Next you'll be arguing over `the photon: wave or particle?'

And as you should be aware, there are specific experiments where a photon
behaves exactly like a particle would.  There are other specific experiments
where it behaves exactly like a wave would.  We weren't discussing abstract
philosphy, we were looking at a specific situation where the distiction
between electrical and magnetic is meaningful.

SR
---
From: mlush@crc.ac.uk (Mr. M.J. Lush)
Newsgroups: rec.arts.sf.science
Subject: DNA garrotte
Date: 18 Aug 92 11:14:20 GMT
Reply-To: mlush@crc.ac.uk (Mr. M.J. Lush)
Organization: MRC Human Genome Mapping Project Resource Centre, Harrow, UK


      
  	Can anyone give an estermate of the breaking strain of DNA,
in say N/cm^2?

        The reason I ask is that I'm working on a race of occult
assassins who kill useing a garrotte made from the victims own DNA,
and I want to know if there's enough in the human body (assuming it
can be non-destructivly removed useing foul means that Mankind-was-
not-ment-to-know),  or will they have to steal some cells and do
a bulk culture.


-- 
Michael

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
NPC rights activist           |      Nameless Abominations are people too.
From: sks1@Ra.MsState.Edu (Sujay Shaunak)
Newsgroups: rec.arts.sf.science
Subject: Evolution under High Gravity
Date: 14 Aug 92 00:10:42 GMT
Organization: Mississippi State University


  
   Hello, I am interested in getting the net.consensus (as if there ever
is one) on the effects of living in a high gravity environment. I have noted
that in *most* SF (at least the I have read), humanoids who live on high
gravity worlds (relative to earth gravity anyway) are typically shorter,
stockier, and stronger.

   I would think that structural and muscular strength would be increased
so that the being could survive on the planet (or whatever). I would
not be so quick on height and stockiness. I would think that since the 
high-g environment would be natural for the being, that other effects
would dictate growth patterns (like : Is basketball a planetary sport :).

   Any other opinions on this ?

Just curious,


--

'Sooge'
sks1@ra.msstate.edu
From: dillard@ccwf.cc.utexas.edu (Alex Dillard)
Newsgroups: rec.arts.sf.science
Subject: Gills and Continuous-flow breathing
Summary: If you could inhale and exhale at the same time, wouldn't you be a
         great singer???
Date: 17 Aug 92 21:58:27 GMT
Organization: The University of Texas at Austin, Austin TX

kuijt@umiacs.umd.edu (David Kuijt) writes:
>us earthbound dudes have.  (Speaking of which--is there any reason
>why lungs couldn't be built on a continuous flow model, evolutionarily?
>Enquiring minds want to speculate!).

fiddler@concertina.Eng.Sun.COM (steve hix) writes:
>One reason is that such a system would require more holes...a more
>complicated system, with new avenues for parasitic invasion, potential
>injury, increased water loss in dry environments, increased access for
>dust/sand/other foreign particles.

   Actually, there are already two holes, the nose and the mouth.  You could
take air in through the nose and send it out through the mouth.  When you
want to eat, just switch to in-and-out breathing through your nose.  The only
other thing you need is to re-plumb the lungs so that they are connected in 
series, rather then parallel.  With this set-up, the air goes in through the 
nose, through the (say) left lung, into the right lung and out the 
mouth.  The individual lungs could pump the air like the heart does, 
requiring valves at either end of each lung.  Finally, you could just 
put a divider in the trachea to divide the incoming and outgoing 
airstreams.  For eating a valve allowing exhalation through the nose is 
needed, but this is not much more complicated than the epploglottis 
which we use to close the trachea when we swallow.

A rough flow diagram:  (where = represents plumbing and =/= is a valve)

   Nose=left trachea=/=left lung=/=right lung=/=right trachea=mouth

   And, just imagine what great singers these guys would make! (once you 
move the voice-box into the right side of their neck)

-- 
 \ _
 - o  We were once so close to Heaven, Peter came out and gave us medals,
  ^   declaring us the nicest of the Damned. - They Might Be Giants
        Alex  dillard@sleepy.cc.utexas.edu
From: m23364@mwunix (James Meritt)
Newsgroups: rec.arts.sf.science
Subject: Re: Evolution under High Gravity
Date: 14 Aug 92 16:01:07 GMT
Organization: MITRE Corporation, McLean VA

In article <sks1.713751042@Ra.MsState.Edu> sks1@Ra.MsState.Edu (Sujay Shaunak) writes:
}   Hello, I am interested in getting the net.consensus (as if there ever
}is one) on the effects of living in a high gravity environment. I have noted
}that in *most* SF (at least the I have read), humanoids who live on high
}gravity worlds (relative to earth gravity anyway) are typically shorter,
}stockier, and stronger.

Add effects on living in LOW gravity, and cross-post to talk.origins.
Velikovsites and Talbottians think that EARTH was once a low-g planet!
From: kellmer@milton.u.washington.edu (Brent Kellmer)
Newsgroups: rec.arts.sf.science
Subject: Dinosauers and Dragons, (mostly dinos)
Date: 20 Aug 92 16:58:00 GMT
Article-I.D.: u.1992Aug20.165800.6811
Reply-To: kellmer@u.washington.edu
Organization: University of Washington, Seattle

Well, I'm glad we finally dropped the idea that dragons came from Dinosauers
Romantic--yes, likely--'fraid not.

To back up what several others have pointed out, dinosauers -- this means ALL
dinosauers, for reasons I'll bring up in a sec -- became extinct approx.
65 million years ago.  Recently (in the past 10-15 years), the evidence as to
why they disappeared has come to light, which also proves why none of them 
survived.

Alvarez et al. from UC Berkeley's Lawrence Livermore labs discovered in the
late 70's (or was it early 80's) that a very thin layer of the element iridium
lies between the Cretaceous and the Tertiary geological periods -- amazingly
enough, at approx. 65 million years ago.  The generally accepted reason for 
this is that a meteorite hit the earth at that time.  The impact (which, 
according to the _Science News_ I received yesterday has been almost positively
pinpoints the impact crater as being on the north part of the Yucatan penninsulaand into the gulf -- 180 km in diameter!) fried much of the vegetation in the
Americas and between the ash from the fires and the dust kicked up by the
meteorite, gave the Earth a night that lasted at least 3 years (the original
nuclear winter).  What this also did was to kill every land mammal (and most
sea animals)                         [this should be land animal^^]
over about 10-20 kg in body weight.  Larger than this could not survive without
their food sources, even if they survived the impact itself.  Only the small
animals (among them the forebearers of most mammals) survived, mostly because
of their small size and their ability to live on carrion.  The reason for the
meteorite has been postulated to come from a comet through out of the Oort    
Cloud by a companion star to the Sun, revolving around Sol at a distance of
about .5 ly, but this is still somewhat contested.

As for man, the earliest forms of _homo_ that can be accounted for are about
4 million years ago, as Johansen and the Leakeys have found in the Olduvai
gorge in sub-saharan Africa  (see _Lucy_ by D. Johanson et al.)  As someone
else on the net just put it, the earliest civilation per se would be in the
Fertile Crescent in the Near East about 7000 b.c.e (Jericho, about 9500 b.p.),
cave painting going back as far as 40-50,000 b.p. (before present), and stone
age tools dating back as far as about 100,000 years ago or more.  

-Brent Kellmer
u.washington.edu


pinpointed to the 
Newsgroups: rec.arts.sf.science
From: singley@helix.nih.gov (Erick D. Singley)
Subject: Re: Merpeople
Organization: (National Institutes of Health, Bethesda, MD)
Distribution: usa
Date: Fri, 14 Aug 1992 13:20:50 GMT

>However, your original problem would presumably be that gills could not support
>a mammal the size of a human, underwater.  (Correct me if not)

>Strange - aren't whales mammals?
--
>Timothy D Little 

Sure, whales are mammals- they breathe air through lungs just like you, me, and
dolphins. I'd have to agree on another poster's comment on tests with super-oxgenated fluid-  *breathing* that liquid was tiring.  It required a lot of fluid
circulation and bubbling within the jar with the mouse to keep the O2 content high enough.

On the other hand, a creature of large body mass and activity that DOES use gills in *current* water conditions (without getting all high tech) would be sharks.
Maybe not the same comparision you'd like to make, but they're bigger then your
everyday goldfish when it comes not O2 need.

Wasn't there a story dealing with genetic engineering of humans with dolphins/and or sharks?  Or am I thinking of Uplift War (which changed the dolphins to talk with us)?

Donno about the Biochem-pathways of fish.  Have to have some good simularities though-  Any good membrane people out there? That the question at stake here (at least for the lung/gill part)- what requirements would a person need, biologically, to 'live' underwater (sea, or lake.. it makes a difference. To make a land-breathing comparision a person drowns in salt, and *suffocates* in fresh
[low conc. of stuff in fresh causes difusion of blood plasma/etc. into lungs; also breaks down linings])  I don't have that Wastewater book on hand, what are
differences in O2 content between 'fresh' (ie pond type) vs ocean.   Those stats for O2 solubility is for *pure* water, isn't it?

Erick
From: tjviv@usmi02.midland.chevron.com (John Viveiros)
Newsgroups: rec.arts.sf.science
Subject: Re: general relativity
Date: 12 Aug 92 16:27:28 GMT
Organization: Chevron


  If you want to measure the different rates of time at various heights
from the earth's center, and eliminate any other simple mechanisms such
as the movement of the clock to a different level (an accelation) you
simply need to do as follows:

   Zero both clocks at the surface of the earth (make them read the
same).  Move one clock down 100 meters (for example) at some constant speed.
Leave this clock for some specified period of time (a day?).  After this
period of time, move the second clock down to the first in the same
manner.  Now Bring them both up together.  Both clocks have undergone
identical accelerations.  The two clocks can now be viewed together (in
whatever manner they do this) and the only difference will be from the
differing lengths of time spent at the lower level.  No need for some
tranfer of information delay.

John Viveiros
Newsgroups: rec.arts.sf.science