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Rosco Bodine
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[*] posted on 4-10-2004 at 15:21
glycine nitrate


While browsing PATR , I found an item
of interest which appears to be a compound similar to urea nitrate , only
more sensitive and powerful . The compound is aminoacetic acid nitrate ,
or glycine nitrate , evidently a simple
acid salt formed by direct combination
of dilute nitric acid and glycine . The
compound is described as a powerful explosive resembling picric acid in its properties . The chemical formula is
H2N-CH2-COOH + HNO3 , mw 138.08 ,
mp ca 145 with evolution of gas .

The detonation proceeds according to
the equation H2N-CH2-COOH-HNO3 ---->
2CO + 3H2O + N2 , releasing significant
amounts of carbon monoxide .

See PATR vol. 1 page A178

Has anyone ever experimented with
glycine nitrate ? It would seem to have
usefulness because of its relatively easy
and cheap manufacture , and may be of
interest in eutectic nitrate mixtures with things like urea nitrate or ammonium nitrate , methylamine nitrate , calcium nitrate , ect .
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[*] posted on 4-10-2004 at 15:50


Funnily enough I recently thought about this, too... but discarded the idea thinking that it probably wouldn't be powerful, but more importantly (to me), hard to detonate.

From my experience with other amine-nitrate salts, I wouldn't think this one is easier to detonate. I guess it has to be tried. Do you have more info on impact sensitivity?

Another interesting amino acid nitrate may be that of arginine, - as it may form a di-nitrate, or even tri-nitrate. (I.e. Arg. is (H2N)CH(COOH)(CH2-CH2-CH2-NH-(H2N)C=NH)
Availability may be more an issue here though.




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[*] posted on 4-10-2004 at 16:12


There is no further information I have
except the brief PATR article which does
give a few references . However if the
properties resemble picric acid , then the
material is not going to be very hard to
initiate in particulate form . It would
likely be similar to picric acid or TNT ,
sensitive as pressed charges , insensitive
when cast . This compound would be more powerful and sensitive than the
glycine - ammonium nitrate double salt ,
which might also be a component in some
sort of cast composite . The material would most likely be acidic similarly to
urea nitrate .
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[*] posted on 4-10-2004 at 16:29


Putting this to the test:

0.5 mole glycine (28.5 g) was dissolved in 150 ml water (its solubility isn't very high), and 0.5 mole HNO3 (48.5 g of 65%) was added slowly, while keeping the solution on ice. Both reagents are analytical.

The solution warms up slowly. As I did previously with other amine nitrates, I added 2 ml of this solution either to acetone, or absolute alcohol. UNLIKE with previous amine nitrates, no precipitation occurred. :(

This is unfortunate, as I am not really keen on boiling the solution to dryness (apart from HNO3 fumes that might be liberated).
I guess I will just put it on a plastic plate, and let it evaporate over the next few days. Hmm. Outside I guess....

Any thoughts?




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[*] posted on 4-10-2004 at 16:51


AW NAW ! not another "ghost in the beaker" reaction ! or "Where's the compound I'm supposed to see" mystery :D

I have no idea what is going on there unless it is affected somehow by order of addition , concentration of acid and
solutions . You could try adding the
powdered glycine to stirred cold undiluted acid and see what happens . Or you might try making a paste of the glycine
with a smaller amount of water and very
slowly adding the d 1.4 nitric acid to the stirred slurry .

Would have to go to the original references from PATR and see what the
journals say about the synthesis .

It may be that the product is there , but
highly soluble , and the only way of getting the solid is by evaporation .
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[*] posted on 5-10-2004 at 06:29


chemoleo ,

A couple of thoughts . As you added the nitric acid , did the glycine then dissolve much more easily , resulting in a rapidly clearing solution ? Was the warming effect
greater than would be expected from an
ordinary dilution of the acid , as would be
an indicator of a chemical reaction ? Have you tried a heat assisted concentration until any crystals appear , and then chilling
to increase the precipitation ? If this acid salt behaves similarly to urea nitrate , being stable and highly soluble in hot solution , and much less soluble in cold ,
then the direct precipitation could be done
by working with a hot concentrated reaction mixture , from which the crystals
begin to precipitate just after the temperature begins falling away from the
boiling point . Precipitation could be completed in the cold , and evaporation
of the residual solution should provide recovery of any remaining product .

The crystals of glycine nitrate should be rhombic plates or needles . The material was prepared in 1820 by Braconnot ,
E.N.Hornsford , Ann. 60 , 26 (1846)
mp given by A.P.N. Franchimont, Rec. 2, 339 (1883) , other references are
Beil 4 , 340 and Thorpe 2 ( old edition 1917) , 467

Let us know what develops after the solution evaporates .

PATR also lists the dehydrated form of glycine nitrate , which it calls "nitroglycine" , and this would appear to be analogous to nitrourea and
nitroguanidine , as the product obtained
when the ordinary nitrate is dehydrated
by dissolving in cold concentrated sulfuric acid and then dumping the solution into cold water . But PATR does not specify the
method used to obtain the "nitroglycine"
as being analogous to that method for
nitrourea and nitroguanidine . PATR does
state that nitroglycine forms explosive salts and specifies that the silver salt of
nitroglycine is explosive . I speculate that
metallic salts of nitroglycine would likely be powerful primary explosives , and this
is very interesting for experimentation , since so far as I am aware anyway , such
compounds have not been mentioned in
online discussion and are pretty obscure
curiosities in the literature , which would seem worthy of examination .

[Edited on 5-10-2004 by Rosco Bodine]

[Edited on 5-10-2004 by Rosco Bodine]
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[*] posted on 5-10-2004 at 07:40


Well I am certain a reaction should take place, why shouldn't it? The reactions between amines and strong acids is normally straightforward.
Apart from that - nitric acid normally smells quite distinctly. However, the glycine nitrate solution is DEVOID of any smell whatsoever.
Regarding solubility, it's probably just that the resultant nitrate is highly soluble. Which is unfortunate, because it almost certainly means it is nice and hygroscopic, so 1) difficult to keep dry 2)tricky to make it dry (due to its energetic nature).

Anyway... I will do it again (while I let the original solution evaporate), and this time with very little water. Hopefully the nitric acid will dissolve any undissolved glycine. I will try and aim for a solution that effectively contains 75% water and 25 % HNO3. This worked nicely when I tried to precipitate other amine nitrates with ethanol. Although I am pretty convinced I won't be able to precipitate it. Lets see :)


PS I am not really keen on hot evaporation, as I just don't know the properties of the stuff. If you found a reference that cited that GlyNitrate was obtained by boiling down a solution thereof, that would help :)




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[*] posted on 5-10-2004 at 08:27


Urea nitrate is extremely soluble , but
the dried crystals are absolutely *not*
hygroscopic , so we cannot be too hasty
in expecting a direct relationship between
solubility and hygroscopicity to hold , even though it often does parallel , it is not an absolute rule . Guanidine nitrate
is similarly highly soluble , but also non-hygroscopic , and hopefully the same may
apply to the related compound , glycine nitrate . Also it is typical for such salts
to be stable in hot solution . But just
the opposite will be true for the dehydrated forms which will be gradually
decomposed by boiling water uneventfully
via hydrolysis . I understand your caution
when heating an unknown solution , but
it is likely that it is relatively safe to boil
a solution of glycine nitrate until crystals just appear and then allow the concentrated solution to cool . Alternately
the glycine could depart at escape velocity
and warp speed its way returning home
to the interstellar regions of the distant
Saggitarius galaxy , leaving a mile wide
crater sans one very surprised researcher :o So you toss a coin and go for it :D
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[*] posted on 5-10-2004 at 08:57


I guess you are right about the safety (or unsafety) of boiling it down. It's just that I had unpleasant past experiences where logic demanded it should be safe, and suddenly it turned out it wasn't.

Anyway... I wouldn't quite compare it ot urea nitrate.
Unlike what you say, urea nitrate isn't very soluble at all, in fact, you can use nitric acid to purify urea from urine ( http://www.sciencemadness.org/talk/viewthread.php?tid=2415 , last post). There, one achieves a 97% yield from 14g urea in about 50 ml of 33% dilute HNO3. Hardly a high solubility, if only 3% (0.5 g UN) dissolve in about 50 ml!
Anyway... this doesn't really matter wrt glycine nitrate. All I am saying it may be dangerous to extrapolate. I will test it anyway...:)




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[*] posted on 5-10-2004 at 09:11


I have kilos of urea nitrate on hand ,
and it is definitely very soluble except
in the cold , very cold .

Another thought relates to the possible
reaction of the nitroglycine with hydrazine sulfate , to possibly form a "nitroaminoglycine" compound similar
to the known reaction for producing nitroaminoguanidine from nitroguanidine .
Such a "nitroaminoglycine" compound , if
it exists , could also form a series of explosive metal salts , possibly having
useful properties .

Any of the three compounds , glycine nitrate , nitroglycine , or nitroaminoglycine
might give products of interest when diazotized with sodium nitrite . So there
definitely are a few experiments which
could be done involving glycine nitrate and
its possible derivatives .

[Edited on 5-10-2004 by Rosco Bodine]

[Edited on 5-10-2004 by Rosco Bodine]
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[*] posted on 5-10-2004 at 14:38


Philou Zrealone where are you :-) We have an experiment, yeah baby..... a science experiment made just for you :-) nitroaminoglycine , does it even exist??

:D:o:D:o:D:o:D:o:D:o:D:o:D:o:D:o:D:o:D

Sorry , I just had to say that again :cool:
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[*] posted on 6-10-2004 at 05:26
Update


Last night I boiled down the glycine nitrate solution to about half of its original volume (100 ml). At that point, the vapours that came off started to smell of HNO3, so I had to stop. To cool, this was placed into the -20 deg C freezer. Tiny needle like crystals could be seen if one looked closely... but they didn't become more after an hour.
50 ml of this was mixed with EtOH (96%), or acetone, and (both 500 ml), and placed in freezer for 10 hours. No crystallisation. At least I am convinced now that the glycine nitrate is truly soluble in these two solvents.
Lateron I shall see what happens if a 25% glyc. nit. solution is placed into the -20 deg C freezer.
If this doesn't work, then I will truly start to wonder how the GN was prepared. Particularly as boiling doesn't seem to work. Oh... I guess one thing I could try is to freeze dry it. BUT... with a potential explosive, and equipment that isnt my own? Hmmm...




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[*] posted on 6-10-2004 at 07:09


Yeah , this is a peculiar result for what should be a simple salt forming reaction ,
and I don't understand the result either .

The original journal articles probably would shed some light on what is needed
to get the desired product . I have encountered these sort of reactions before which would seem so simple and then prove to be just the opposite in a way that challenges the confidence one has that any proposed synthesis is "simple" just because it seems like it should be . There is probably some factor of temperature or pH or some variable to
which the reaction is sensitive , or some
competing side reaction which is complicating things . I don't know what
to suggest , and for guessing , well your guess is as good as mine . I have a list
of "reactions to do" longer than my list
of experiments done and reagents on hand , but this reaction is getting added to my list of "mystery" reactions to study
further and see what's up with the
"anomalous" results . Nothing like a mystery for curious minds .
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[*] posted on 6-10-2004 at 13:22


Have you tried salting the stuff out? That should be much safer than boiling it.
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[*] posted on 6-10-2004 at 14:23


Salting out is a good idea , but the most
likely candidate would be ammonium nitrate , and there is the potential then
of forming the glycine - ammonium nitrate
double salt , or a ternary complex , which
is an interesting possibility unto itself .

Calcium nitrate is another possibility , but
has the same potential .

Given the isolation difficulty, I think when I try this I will likely just make a paste of a portion of the glycine , add the nitric acid
dropwise to get a warm slurry for a small working volume , and then concurrently
add the remaining glycine in small portions
keeping pace with the addition of nitric acid . If some crystallization can get started in the more concentrated mixture
as it cools , then the mixture can be poured into a large pyrex casserole tray
in a shallow layer for evaporation of the
remaining water . A heating pad for low
heat and a fan blowing air across the tray
should speed the drying .
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[*] posted on 6-10-2004 at 17:35
Success!!


I now have ± 30 g of glycine nitrate!

Indeed, it was all a matter of temperature and concentrations.

0.5 mole glycine (28.5 g) was added to 30 g of water, and to this 0.5 mole HNO3 (48.6 g of 65%) was added.
Of course the glycine didnt dissolve in the 30 g of water, but as soon as I started adding HNO3, the undissolved glycine would literally disappear where I added the HNO3 (indicating of course that a reaction was taking place).
The solution also heated up rapidly, to about 70 deg C. Once all the HNO3 was added, all the glycine was dissolved. Then this was put on ice, and then into the -20 deg C freezer. Crystallisation ensued! Lots and lots of it. The crystals are kind of squarish flat, and reflect light nicely. About the size of sugar grains by the end of it.

This was filtered off, and the crystals collected. Of course I had to test it with ethanol - and surprise surprise, no dissolution! I guess this is because previously I always had a fair amount of water present, preventing crystallisation.
Anyway, the crystals were washed with ethanol, and now they sit in a plastic container, still sort of moist. It will be kept outside... just in case.

Hygrocopicity: NOT really noticeable! a spatula of cyrstals actually dried, rather than getting wetter.

Friction test: No effect, when putting the moist stuff onto a metal plate and scraping it.
A few crystals were put onto the hotplate, and heated a bit... so that it was just too hot too touch. Crystals are definietley dry. Rubbing them onto the plate with a metal spoon didnt do anything (good!), and neither did the heat. Tapping it hard with the spoon didn't do anythign either - also good.
At last, under the flame (on a spatula), it would melt, and then decompose, leaving a black residue. No obvious flame.

It's all good, it seems easy & safe to handle (which was my main worry).

What to do with it now? From previous experience with amine nitrates, they are damn hard to initiate, even with several grams of HMTD. In fact I cannot report success.

Hmm, anyway, will try to melt a small amount and see whether thats possible without decomposing it. But this is stuff for the weekend. I might subject it to a bit of thermite, maybe heatshock does the job :)

PS yields are not ideal... but i didnt bother concentrating the mother liquor, plus lost lots during filtering/handling. Clumsy me ;)

[Edited on 7-10-2004 by chemoleo]




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[*] posted on 6-10-2004 at 18:00


Hot Damn ! That is good news . I was worried for awhile there that this might be a bust , and thinking WTF is wrong , there should be an avalanche precipitation
of crystals dropping out of this reaction , almost like a setup of expanding plaster
threatening to crack the beaker , and yet you were getting only a whole lot of nuttin' instead , for all my headscratching
and wondering . Okay I'm feeling better now :D

Have you tried putting some of the crystals on an "anvil" or equivalent and
giving it the old hammer test ? Not necessarily a definitive test but a good
snap or bang can be a good sign of easy
detonability .

I have successfully detonated urea nitrate
which is likely less sensitive than will be the glycine nitrate . My experience with
urea nitrate is that a threshold amount
of HMTD is 2.5 grams , 9mm diameter column hand pressed in a polypropylene
5ml culture tube 12mm OD X 75mm L .
3 grams HMTD would be about right for
sure detonation of urea nitrate . A good
compound detonator with 2.5 grams of
picric acid or equivalent base charge gives
guaranteed success . The glycine nitrate
should be more easily detonated than urea nitrate , and about a third more powerful , perhaps a rough equivalent to
TNT or a little better :D and a whole lot
cheaper and easier to produce . Hmmm ,
this really could have interesting possibilities .

[Edited on 7-10-2004 by Rosco Bodine]
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[*] posted on 6-10-2004 at 22:01


chemoleo ,

This material is pretty unknown so regard
all of this as theoretical and experiment
with caution .

There is an idea for what you could do with a small sample of your glycine nitrate . Try to convert it to nitroglycine , which should be soluble in acetone .

Since there is no method described ,
possibly use the same method as for
nitrourea or nitroguanidine . Dissolve
the glycine nitrate slowly , added gradually in portions to stirred *ice cold*
concentrated H2SO4 and pour the cold , probably milky solution over crushed ice
to precipitate the nitroglycine .

See if dripping in a concentrated solution
of silver nitrate or lead nitrate into an
acetone solution of nitroglycine results
in a product that is a primary explosive .
Some water may be needed to be added
to the acetone solution of nitroglycine to
create a "solubility interface" to bring about this reaction . Or a plain aqueous
solution may work at moderate temperature , but not too warm or the
nitroglycine will possibly be decomposed .
Nitroguanidine can actually be recrystallized from boiling water for example , but nitrourea is decomposed ,
and what stability nitroglycine would
have in hot water is absolutely unknown .

Nitroaminoglycine and its salts could be
a further experiment .

[Edited on 7-10-2004 by Rosco Bodine]
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[*] posted on 7-10-2004 at 02:25


Quote:
Originally posted by Rosco Bodine
Since there is no method described...

Might mean more to chemoleo then us --> <a href="http://ww1.altlist.com/~58717/pulse.altlist.com/images/nitroglycine-german.jpg">nitroglycine</a>

Translation?<br>
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Rosco Bodine
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[*] posted on 7-10-2004 at 06:17


Good link , translation of interest indeed .

also called nitroaminoacetic acid or
perhaps ? nitraminoacetic acid , so
that is the stuff .

My German is humiliatingly poor so I
would pick at that article for days to get the gist of it .

Is Rhadon around ? He has a talent
for these translations .

[Edited on 7-10-2004 by Rosco Bodine]
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[*] posted on 7-10-2004 at 11:54
Translation


The first paragraph goes on about nitramine acetic acid ether - but as I don't quite know what it is, I shall refrain from translating it. It seems though that nitramino acetic acid is prepared from the ether. Any ideas? Unfortunately, no mention is made of the procedure to add the glycine nitrate to conc. H2SO4.

Then, starting from nitramino acetic acid ("Nitraminessigsaure";):

Nitramino Acetic Acid (NAA, HOOC-CH2-NH-NO2) crysallises in long needles, melts & decomposes at 103-104 deg C, is not much soluble in cold, but easily solubilised in hot water; it is also soluble in EtOH, diethylether and acetone, but not much in chloroform, benzene and ligroin (don't know what that is). It's a double basic acid (?).
Salts of NAA: The potassium salt explodes mildly upon heating, and it precipitates with Pb and Hg salts, which redissolve in the presence of more nitramine salt.
The corresponding Ag salt turns dark in light, decomposes in boiling water while producing a silver mirror, and explodes upon heating (the dry substance presumably).
The copper salt precipitates when boiling up a solution of NAA with copper carbonate, in the form of very beautiful blue crystals. It is not much soluble in water, acidic, and turns green when heated (it forms the dihydrate). The salt cannot be turned into the anhydrous form via heating due to concomittant decomposition.
Both free NAA and the salts produce a red colour with iron chloride (it doesn't state which, i.e. II or III chloride).
Heating NAA on its own up to 125 deg C leads to its decomposition, partly into CO2, NOx, CH3OH and an unidentified liquid residue.

Looks like, whoever is to make this, won't have trouble identifying it. But by this description it doesnt look like that NAA could be used for more than primaries.




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[*] posted on 7-10-2004 at 12:38


The described properties seem to indicate
nitroglycine is more comparable with nitroguanidine than nitrourea , because
nitrourea is not heat stable and decomposes even in warm water .
Nitroglycine could actually be a stronger high explosive than nitroguanidine ,
with heat stability better than nitrourea ,
but somewhat less than nitroguanidine .

The dibasic acids are neutralized by two
+1 valency alkali atoms , for example
styphnic acid is dibasic , picric acid is
monobasic .

The lead salt or other heavy metal salts
may be interesting , and it looks like
such salts could be formed in aqueous solution with no problem .

[Edited on 7-10-2004 by Rosco Bodine]
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[*] posted on 7-10-2004 at 17:23
Nitramino acetic acid ?


Ok, 11 g of dry glycine nitrate was slowly added (30 min) to 23 ml of 98% H2SO4. The nitrate seemed to dissolve, the first few additions left the solution clear. Lateron, it turned milky-clear, but I am not sure whether these were tiny bubbles.
After all was dissolved, this was put into 150 ml ice water. No immediate crystals :(.
It's now in the fridge, let's see what it looks like tomorrow ...

PS proportions of H2SO4 over crushed ice are roughly those of COPAE

[Edited on 8-10-2004 by chemoleo]




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[*] posted on 7-10-2004 at 19:18


That should be more than enough H2SO4 .

I extrapolated the proportions as compared with the COPAE description for
nitroguanidine to apply to nitroglycine .

And for your 11 grams of glycine nitrate ,
considered on a molar basis , you would
have required 12.2 ml H2SO4 , and then
after dissolving that amount of glycine nitrate in the cold acid , kept below 10 C ,
dumped it over about 75 grams of crushed
ice in a prechilled beaker . Those are more economical quantities for larger batches if the solubilities and other factors permit .

I made nitroguanidine once many years ago , and I don't recall for certain but IIRC
the precipitation of product was fairly rapid when the mixture was dumped over the ice .
I do recall that I recrystallized
the product from boiling water , and that
the nitroguanidine crystallized out as long
hard , but tough and flexible needles , having a distinctly springy plastic quality like hard nylon bristles which had been pulled from a scrub brush . The peculiar material was a very bright glistening white color . Such a crystalline form is
undesirable for press loading , and I hope the crystals of nitroglycine are a more
usual and compact geometry . Sometimes
a subsequent crystallization from a different solvent is used to get crystals
in a form that is desirable .
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[*] posted on 7-10-2004 at 20:16


Yes, I know I used more H2SO4 than in COPAE.
I did it mainly because I wanted to have a large excess of it, to make sure its dehydrating power comes to full force. Also, because the mixture became rather thick. At last, I reasoned an excess shouldn't matter as the amine nitrate is added in small portions... indicating that the reaction isn't really stoichiometric in the sense that precisely one molecule of H2SO4 is needed, no more and no less. I can't see why an excess of H2SO4 could hurt basically.
The description of the German article says it's not much soluble in cold water. I thought, at least when the reaction mix is slowly layered into the the H2O, I should see preciptiation / crystallisation at the interface, regardless... but I didn't. :(
I will try it again, with much much less water next time. But I don't think it will work... but lets see first.

Another problem is, as long as it doesn't crystallise, it will prove rather hard to show that I really did obtain nitramino acetic acid. Regardless of the cation I add (Fe, Cu, Ag, Pb), it will first react with the remaining H2SO4, forming precipitates (or not), thus interfering with determining whether I got NAA or not.

Let's see, shall try it again with extremely restrictive conditions. If it doesn't work then... I will give it a rest, and play abit with the glycine nitrate itself.




Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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