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-   -   Agenothree (HNO3, nitric acid) (http://forums.srellim.org/showthread.php?t=3064)

Kath Sep 11 2006 10:19 AM

Re: Science of Pern
 
Quote:

Originally Posted by edith (Post 47996)

Minerals
SOP: Aluminium?

I'm pretty sure there are references to Bauxite (i.e. aluminium) in DDawn, as well as the rest of the rather limited mineral wealth of Pern.

As far as HNO3 goes, flamethrowers were developed in DDawn, but I'm not sure if they describe what chemicals were used in those ones or not. Although isn't that the first place we here HNO3 slurred into agenothree?

Brenda Sep 11 2006 05:03 PM

Re: Science of Pern
 
I don't think we hear "agenothree" in DDawn, but we do hear it in DE/RSR during the ground crews' flamethrower drill.

Chimaerrha Sep 11 2006 05:13 PM

Re: Science of Pern
 
You do.

DD online:

Quote:

“Now, a sweep from bow to stern in a one-second blast chars as much Thread for the range of these throwers. Catch the end of the stuff and fire runs back up most of it. Don’t waste the HNO3.” His rapid-fire use of the chemical designation made it sound more like “agenothree,” Sallah thought, losing concentration once again. Damn, she must pay attention, but she was so used to listening for sounds, not words.
Quote:

“. . . and make each cylinder last as long as possible,” Drake was saying. “Conserve agenothree and power, and you’ll last longer in the flight line. Which is where you’re needed. Now, most of you have had experience with turbulence

P'ter Sep 12 2006 02:03 PM

Re: Science of Pern
 
If I am reading correctly, the books ALL imply that the HNO3 was not just sprayed as a mist/vapour (although it WAS used as a liquid in AWOP to erode the anti-matter engines) but was ignited to produce flame. HOW?

Brenda Sep 12 2006 04:19 PM

Re: Science of Pern
 
Okay, thanks Chi, that was the quote I remembered. Drat! Wrong book again!

Kath Sep 13 2006 03:57 AM

Re: Science of Pern
 
Yep, that was the one I was thinking of as well. I first read -Dawn round about the same time as I started using HNO3 in chemistry, and the memories of those passages have stuck fairly well. Needless to say, it was way before RSR got published....

edith Sep 14 2006 06:43 AM

Re: Science of Pern
 
In RSR it's described as one of 2 liquids. It is an oxidising agent. But you'd need 2 tanks and it's pretty corrosive stuff so everything would have to be lined somehow, I did a diagram of fandarel's machine (which I need to re-draw) and I lined everything that came in contact with it with enamal- I'm assuming they had enamel or the metal tanks wouldn't last long- not would the pipes! But it all seems over-complicated if you look at other flame throwers which use a flamable liquid or gas (Mum's Organic Gardening magazine is full of them)

But fandarel's machine, which, despite the enthusiasm that was shown for it in DF sprays HNO3 directly on the Thread.

granath Sep 15 2006 01:04 AM

Re: Agenothree (HNO3, nitric acid)
 
There is conflicting information about what the flame-throwers really are: in some books they talk about a fine mist, in others it's definitely a flame. I seem to remember a six-meter flame at least mentioned in either DD or RSR. Probably DD just after they're so disappointed golds can't ingest firestone. Maybe someone with access to e-books could look it up?

There are other mentions of HNO3 being a great fertilizer, and this definitely implies a spray rather than a burn. Although I suppose thread ash could be a good fertilizer as well.

edith Sep 15 2006 03:51 AM

Re: Agenothree (HNO3, nitric acid)
 
as far as I can remember...
in DF they are trying to make a flamethrower but Fandarel comes up with a device that sprays HNO3 instead which impresses D'ram as it's a little bit safer.
In ATWOP theres a reference to it being nitric acid in the flame throwers
and in RSR there's a reference to 2 chemicals being used, one of which is nitric acid.

thats all I've got in my database but I may have missed something!

Spaceman Spiff Sep 15 2006 05:05 AM

Re: Agenothree (HNO3, nitric acid)
 
Didn't the queen riders carry flame throwers as well? I could have sworn they carried them in the 9th Pass as well and shot out flame, not just spraying the chemical...

Becky Sep 15 2006 09:53 AM

Re: Agenothree (HNO3, nitric acid)
 
Spiff, I was thinking the same thing while reading this. Queen riders do use flame throwers. And Edith is correct that D'ram thought the HNO3 sprayers were safer, they didn't have them in his time. So I'm thinking that eventually both were used.
Maybe HNO3 was used over crops and forested areas to help fertilize and keep the plantings safe. Flamethrowers by queen riders and also ground crews over rocky, weedy areas that could take a good burning.

Chim Sep 15 2006 01:40 PM

Re: Agenothree (HNO3, nitric acid)
 
TWD online:

Selianth wants me to stay above her at all times so her flamethrower won't singe me, Ruth said, his mental tone muffled as he retained fire-breath. He altered his position and now all the wings began to move.

They had fire.

Spaceman Spiff Sep 15 2006 05:21 PM

Re: Agenothree (HNO3, nitric acid)
 
Quote:

Originally Posted by Becky (Post 48506)
Spiff, I was thinking the same thing while reading this. Queen riders do use flame throwers. And Edith is correct that D'ram thought the HNO3 sprayers were safer, they didn't have them in his time. So I'm thinking that eventually both were used.
Maybe HNO3 was used over crops and forested areas to help fertilize and keep the plantings safe. Flamethrowers by queen riders and also ground crews over rocky, weedy areas that could take a good burning.

That makes sense :D

GirlSlick Sep 15 2006 06:09 PM

Re: Agenothree (HNO3, nitric acid)
 
Just want to put in here, because the nitric acid/flamethrower issue is something I've run across in passing in my recent reading - I think Anne has confused the two different methods of Thread-destruction with each other.

HNO3, as I understand it, isn't flammable - it's corrosive. Fandarel's agenothree sprayer literally sprayed a mist of nitric acid to destroy Thread. The flamethrowers that the Oldtimers brought forward to the Ninth Pass used a flammable fuel to burn Thread either on the ground or from dragonback. But in the Second Weyr, when Torene is contemplating her flamethrower tanks, she muses that - "sometimes a fine spray was blown back before the HNO3 ignited". The same confusion between an acid sprayer and a flamethrower crops up in Moreta.

I'm not a scientist, so please do correct me if I'm barking totally up the wrong tree - but it looks to me like Anne has mixed up the two contraptions.

edith Sep 16 2006 09:11 AM

Re: Agenothree (HNO3, nitric acid)
 
oooh....
I just found this in Wikkipedia.

Quote:

Reactions of nitric acid with many organic compounds, such as turpentine, are violent and hypergolic (i.e., self-igniting).
at http://en.wikipedia.org/wiki/Nitric_acid

granath Sep 16 2006 04:38 PM

Re: Agenothree (HNO3, nitric acid)
 
Nitric acid wouldn't burn on its own, but combined with another compound it would self-ignite, as Edith said. That would mean it'd be possible to use agenothree as a flamethrower fuel, but only by combining it with something else, such as turpentine.

GirlSlick Sep 16 2006 06:09 PM

Re: Agenothree (HNO3, nitric acid)
 
Okay...just dug up another HNO3 reference in RSR/D'Eye, when they're practising flaming "Thread" on the ground (actually ropes dropped over a cliff). There's talk of a mix of two gases being used to create the flame, which is different again to the Second Weyr reference, which speaks of a fine spray of HNO3 which ignites.

The Wiki reference is interesting, but since the Pernese were so anal about routinely calling the substance "HNO3" in the first place (when 'nitric' or just 'acid' would have been a more workaday term), wouldn't they have specified "the HNO3/turpentine mix" (or whatever) in the first place if it were a combination of two? Is turps good for crops? If, presumably, the two liquids have to be kept in separate tanks, why do we only ever heard about agenothree and never the other stuff? Why would you go out of your way to create what sounds like a potentially nasty sort of chemical reaction to make fire when a simple fuel/thrower combination would work just as well and require substantially less chemistry to manufacture the two substances?

Maybe I'm just a cynic, but I can't help thinking Anne didn't put that much thought into the science of agenothree/flamethrower mechanics...

Oldwolf Sep 17 2006 03:39 AM

Re: Agenothree (HNO3, nitric acid)
 
with regards to linings , Manora asks F'nor to take a lined numbweed pot to Smithhall because of discolouring of the numbweed and ask if its safe ( just before F'nor is wounded in a duel over a knife made for a wedding

Nick

Cheryl Sep 17 2006 08:26 AM

Re: Agenothree (HNO3, nitric acid)
 
Quote:

Originally Posted by GirlSlick (Post 48580)
Maybe I'm just a cynic, but I can't help thinking Anne didn't put that much thought into the science of agenothree/flamethrower mechanics...

What, you're suggesting Anne didn't research and plot out the science in nitty-gritty detail in advance? Say it isn't so! :roll:

edith Sep 17 2006 09:36 AM

Re: Agenothree (HNO3, nitric acid)
 
I was thinking about this.
At first glance it does seem stupid, but on further reflection it makes sense to have a self-igniting flamethrower on dragonback at least.

Nerami Sep 24 2006 07:43 AM

Re: Agenothree (HNO3, nitric acid)
 
This is going a few years back so bear with me...

It was whilst I was studying my first year of HNC Science ( chemistry). I was speaking to one of my lecturers, just general chit-chat. The chap, a Dr. Nigel Freestone, is exceptionally smart, and something of an authority on transition metals...

Anyway, I asked him if nitirc acid was flammable, and got an unequivocal yes in reply. I explained why I'd asked the question, telling him about the Pern books and how HNO3 was used as a flame thrower fuel. He didn't contradict me, so I guess that agenothree is a suitable fuel

Brenda Sep 24 2006 05:26 PM

Re: Agenothree (HNO3, nitric acid)
 
Did you have a point to make there?

Chimaerrha Sep 24 2006 05:29 PM

Re: Agenothree (HNO3, nitric acid)
 
Yes: each quote does indeed confirm that agenothree burns, which we were trying to prove.

Brenda Sep 24 2006 05:41 PM

Re: Agenothree (HNO3, nitric acid)
 
Quote:

"That would burn your skin as quick as pure agenothree,” he exclaimed. “Based on that solution, too. Now, observe. these tubs contain blocks of metal, one each of zinc and copper, in a watered solution of sulfuric acid which makes the metal dissolve in such a way that a chemical reaction occurs.
Quote:

"Now, look here, Aivas," Fandarel began. "I know the rate at which agenothree corrodes metal-"
That's acid burn, corrosion - not combustion and flames, which is the burning currently under debate. There is no debate that HNO3 is nitric acid.

Chimaerrha Sep 24 2006 05:55 PM

Re: Agenothree (HNO3, nitric acid)
 
Ooooooh. That makes sense. Thanks.

GirlSlick Sep 24 2006 06:30 PM

Re: Agenothree (HNO3, nitric acid)
 
A bit of Googling ("nitric acid + flammable") reveals that nitric acid itself is not flammable. A spray of the stuff wouldn't burst into flame. It is an oxidiser - that is, it contributes oxygen to reactions that include flammable or combustible materials.

It's highly corrosive to metals and organics, which fits with it being used as a corrosive rather than flame-based weapon against Thread - but they'd have to line the tanks with something non-reactive.

I'm not sure I'd want to be using it airborne with a dragon underneath me, though - the wind would surely blow the stuff back onto me and/or my dragon, which doesn't sound very pleasant.

Anyway, there's a PDF at http://click.ucdavis.edu/safety/Chem...ricAcidUse.pdf which describes the properties of nitric in detail - it's an interesting read when considering Pern's use of "agenothree"!

Shalyn Sep 24 2006 06:58 PM

Re: Agenothree (HNO3, nitric acid)
 
I'd really like to know what they used.

It seems that the HNO3 won't work properly, since being a corrosive acid, if it were strong enough to eat Thread in the air, then it would be strong enough to do damage to its own tanks and to the humans and dragons using it.

Once the Thread is on the ground, a super-soaker would work just as well as the fertilizing agent.

As for a flamethrower, using some type of oil or fuel - flamable liquid - plus an 'ignition switch' would be good. A butane lighter comes to mind. Problem is - what happens if your flint is a bit low? Remember that story about the guy who bets that the kid's lighter won't light ten times in a row? Kid wins, he gets a Mercedes. Kid loses, he loses his pinkie finger.

I'm just wondering how the flamethrowers work - if there are times that you have a clump of thread in front of you, try to ignite your thrower, and nothing.

Chimaerrha Sep 24 2006 07:19 PM

Re: Agenothree (HNO3, nitric acid)
 
Something I wonder about...

Moreta online:

Quote:

Next Moreta checked the gauge on the agenothree tank, made sure the nozzle head was clean, and strapped on the tank. Then queen and rider moved out to the ledge. On the one above, Holth and Leri were already waiting.
Moreta waved to Leri and received a jaunty salute. Settling her eyepieces, Moreta fastened her helmet, hitched back the cumbersome flamethrower, and mounted Orlith. With a mighty heave, Orlith launched herself toward the Rim.
...

How cumbersome is it? Isn't it kinda shaped like a trumpet?

Shalyn - as to a button to press, this might help:

moreta on.

Quote:

She flicked open the nozzle of the flamethrower, leaning well left in her fighting straps as Orlith came up under the tangle. She pressed the button. The gout of fire found its mark but Moreta also had a blurred vision of blue wings and belly. "Too close, you fool. Who was that?"...She slowly clambered on insensitive soles toward the blackened area, her finger ready on the flamethrower's ignition button. She began to sense the residual heat of the two flame attacks on the rock and moved forward more slowly as much to revive her cold feet as to be cautious. She never liked to rush in on a Thread site, not on foot. However, it had to be done and the sooner the better. Thread burrowed into any crevice or cranny.

Quote:

The wind yanked at Moreta's body and she tugged briefly to settle the flamethrower strap on her shoulder. Now the wind carried with it tiny flecks of black charred Thread. On a stormy day, sometimes her eyepieces would be covered by a muddy film. They were under the first edge of Fall now.
..

edith Sep 25 2006 06:04 AM

Re: Agenothree (HNO3, nitric acid)
 
Shalyn. HNO3 doesn't corrode glass so lined tanks could be used. I did some work on this but I haven't posted it yet.

Shalyn Sep 26 2006 11:37 AM

Re: Agenothree (HNO3, nitric acid)
 
Quote:

Originally Posted by edith (Post 49229)
Shalyn. HNO3 doesn't corrode glass so lined tanks could be used. I did some work on this but I haven't posted it yet.

OK - so the tanks would be fine. But what about the people and the dragons? That is, by using it in the air.

P'ter Sep 26 2006 03:19 PM

Re: Agenothree (HNO3, nitric acid)
 
There are probably some ceramic linings as well.

Brenda Sep 28 2006 06:12 PM

Re: Agenothree (HNO3, nitric acid)
 
I'm pretty sure I remember some mention of ceramic linings, somewhere...

Chimaerrha Sep 28 2006 09:34 PM

Re: Agenothree (HNO3, nitric acid)
 
Quote:

The messenger also confided to F’lar that the Mastersmith was having difficulties with his distance-writer. All wire must be covered with a protective tubing or Thread cut right through the thinly extruded metal. The Smith had experimented with ceramic and metal casings but he could turn neither out in great or quick enough quantity. With Threadfall coming so frequently now, his halls were besieged with demands to fix flame throwers which clogged or burned out. Ground crews panicked when equipment failed them mid-Fall and it was impossible not to accede to every urgent request for repair. The Lord Holders, promised the distance-writers, as links between help and isolated Holds, began to press for solutions. And for the ultimate – to them – solution: the proposed expedition to the Red Star.
Maybe you meant this?

DQ online.

edith Sep 29 2006 11:00 AM

Re: Agenothree (HNO3, nitric acid)
 
Quote:

Originally Posted by Shalyn (Post 49301)
OK - so the tanks would be fine. But what about the people and the dragons? That is, by using it in the air.

Queens fly on the lowest level, you fly low and wear protective clothing-as they do!

Shalyn Sep 29 2006 01:03 PM

Re: Agenothree (HNO3, nitric acid)
 
Quote:

Originally Posted by edith (Post 49581)
Queens fly on the lowest level, you fly low and wear protective clothing-as they do!

From the descriptions I've read about protective clothing, it protects the eyes, and most of the person. Faces are described as "windchapped", so they don't have anything on some parts of the face.

Dragons don't fly with goggles or protective clothing. So they are still not protected. Now, flamethrowers seem to be combersome, and I believe the nozzles are pointed down (which also seems idiotic - queenriders can't char Thread until it's past them? Seems inefficient.) But pointed down would work for agenothree sprayers - less chance of being hit by corrosive acid.

However, wind is a tricky little point of nature. The least little gust can have something going down come back up. So the dragon still isn't all that safe.

Plus, even protective clothing . . . I don't know. If I'm wearing anything that gets sprinkled or saturated with acid, I don't know that I still want to be wearing it. And if it gets sprinkled or hit over and over again . . . it still doesn't seem like a good way to fight Thread.

edith Sep 30 2006 06:04 AM

Re: Agenothree (HNO3, nitric acid)
 
It's not particulry. And the HNO3 sprayer was designed to be used on the ground wasn't it- as this was DF. How a flamethrower might work would be using the oxidising properties as a sort of lighter to light the flammable liquid, so, possibly, once there's a flame there doesn't have to be anymore used in that flame. I'll have to check though.

Oldwolf Sep 30 2006 09:24 AM

Re: Agenothree (HNO3, nitric acid)
 
can i suggest looking how a flamethrower from WW2 works?

Chimaerrha Sep 30 2006 01:17 PM

Re: Agenothree (HNO3, nitric acid)
 
Quote:

Originally Posted by Shalyn (Post 49607)
From the descriptions I've read about protective clothing, it protects the eyes, and most of the person. Faces are described as "windchapped", so they don't have anything on some parts of the face.

Dragons don't fly with goggles or protective clothing. So they are still not protected. Now, flamethrowers seem to be combersome, and I believe the nozzles are pointed down (which also seems idiotic - queenriders can't char Thread until it's past them? Seems inefficient.) But pointed down would work for agenothree sprayers - less chance of being hit by corrosive acid.

However, wind is a tricky little point of nature. The least little gust can have something going down come back up. So the dragon still isn't all that safe.

Plus, even protective clothing . . . I don't know. If I'm wearing anything that gets sprinkled or saturated with acid, I don't know that I still want to be wearing it. And if it gets sprinkled or hit over and over again . . . it still doesn't seem like a good way to fight Thread.


This may help...

M'reta online:

Quote:

The wind yanked at Moreta's body and she tugged briefly to settle the flamethrower strap on her shoulder. Now the wind carried with it tiny flecks of black charred Thread. On a stormy day, sometimes her eyepieces would be covered by a muddy film. They were under the first edge of Fall now.
Quote:

The queens' wing took the final position, sweeping as close to the ground as they safely could. Their slower glide, their more powerful wings gave them more flight stability in erratic wind currents.
Quote:

The queens' wing reformed, flying north, fanning out as gobbets of loose Thread Fell in a curious order caused by the dragon's distortions of the air currents. That was work indeed for the queens

edith Sep 30 2006 01:33 PM

Re: Agenothree (HNO3, nitric acid)
 
Quote:

Originally Posted by Oldwolf (Post 49676)
can i suggest looking how a flamethrower from WW2 works?

I asked Nick how the Churchill Crocodile tank worked and that used a spark, he said that using an oxidising agent was dangerous, so whether that meant that something else used that system or whether he just thought it was rediculous, I'm not sure!

P'ter Sep 30 2006 05:06 PM

Re: Agenothree (HNO3, nitric acid)
 
None of the ones I've been able to find used hypergolic fuels (though NASA does for a lot of its rockets).

The early Italian ones used fuel oil + nitrogen as a propellant. the current U.S. ones use oil + benzine as both propellant and accelerant.

Old ones used anything from fuse cord to blank cartriges for the ignition (the U.S. Navy is known to have actually used Zippo lighters). Current ones use a bettery driven spark plug.

Tank (and boat) mounted ones were just much bigger but just as crude.

Try "lone sentry.com" & "howitworks.com".


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