HDTenEightyP/NetNews huggingface dataset:
From: pgravel@nap.amoco.com (Philip L. Gravel)
Subject: Re: the TRUTH about Methylene Chloride
Reply-To: pgravel@nap.amoco.com (Philip L. Gravel)
Organization: Amoco Corporation
Date: Thu, 27 Aug 1992 18:37:58 GMT

In article <BtMJ3q.L82@wsrcc.com>, alison@wsrcc.com (Alison Chaiken) writes:
 
>                                                              As a
> solid-state physicist, I am nearly completely ignorant of practical
> chemistry, so I took the warning labels on all the solvents very
> seriously.  The methylene chloride one terrified me; it was clearly
> rated as much more dangerous than TCE or toluene!

Get a bottle of reagent grade sodium chloride or washed sand and read the 
labels on them.  You'll be terrified of them too!!!  That's part of the 
problem we have.  Substances that we have used, eaten, and been exposed to 
for millenia are suddenly being labelled as harmful.  No wonder the public is 
terrified of anything that has to do with "chemicals".  Perhaps we should ban 
them all.  Let's see, we can start with dihydrogen oxide (sounds pretty 
awful, but it's only water), move on to sodium chloride (common table salt), 
sucrose (sugar), not to mention nitrogen, oxygen, silicon dioxide (sand), 
etc.  The list of chemicals in our envrionment is *literally* endless.  
Sigh.....


Phil

-----
Philip L. Gravel                      Internet: pgravel@nap.amoco.com
Amoco Corporation, Chicago, IL        Phone:    (312)856-3553
----------
These opinions aren't worth the paper they're written on and
certainly don't reflect those of my employer.
Newsgroups: sci.chem
From: tony2@prefect.uucp (21131-gozdz)
Subject: Re: Azide Chemistry
Organization: Bellcore, Livingston, NJ
Date: Mon, 31 Aug 92 02:21:16 GMT

In article <y9gn-sn.ladasky@netcom.com> ladasky@netcom.com (John J. Ladasky II) writes:
>In article <useless number> saj@chinet.chi.il.us (Stephen Jacobs) writes:

>>I just wouldn't want to do it this way.  Could you maybe displace a benzylic
>>chloride or tosylate with azide in DMSO or liquid ammonia?  Not totally safe
>>either, but it scares me a lot less.
>>
                        [stuff deleted]
>		
>	I am more interested in the general applications of adding azides
>to molecules, however, so if synthesizing something from scratch, I would
>certainly consider the safer method suggested by Steve.
>-- 

                        [stuff deleted]

The modification I'd like to suggest is probably not
too useful for making azidoethidium chloride from its
chloromethyl derivative, as the latter is probably less common,
but should be easy to apply to synthesize many other
benzyl azides. It involves the use of phase-transfer
catalysts, such as 18-crown-6 with KN3, or the smaller
15-crown-5 with NaN3, or various quaternary ammonium
salts (Bu4N+Cl-), the reaction being carried out in
low-boiling, less-polar, and easier to work with solvents.

I don't recall seeing this particular reaction in the
literature, but it's been 11 years since I stopped
dabbling in its variations... Check it in CA under
phase-transfer catalysis or look for a book by Gokel
(?) on the subject. There were also other I can't
remember :-(.

Tony

-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
Antoni S. Gozdz                tel  (908) 758-2931  |  Bellcore  NVC 3X-261
tony2@prefect.cc.bellcore.com  FAX  (908) 741-2891  |  Red Bank, NJ 07701, USA
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Newsgroups: sci.chem
From: robin@ruchem.ru.ac.za
Subject: Re: Ecological effect of dyes
Reply-To: robin@ruchem.ru.ac.za
Organization: Rhodes University, Grahamstown, SA
Date: Wed, 26 Aug 1992 14:50:29 GMT

Hi Greg, why didn't you asl your friendly neighbourhood chemists first?
your question reminds me of a recent scam involving highly-coloured
ornamental fish originating somewhere like Hong Kong, which a)cost a
bomb b)quickly faded to their natural transparent silver colour (they
were freshwater tropical fish) and c)boringly vrekked; Isaw this on
SATV.
There are probably such dyes, food colouring is a possible source,
guaranteed non-toxic. I would think the aquatic life might need some
persuasion, though.
Robin English Chemistry
Newsgroups: sci.chem
From: userDHAL@mts.ucs.UAlberta.CA (David Halliwell)
Subject: Re: Carburetors, gasoline, and why I don't recycle
Organization: University Of Alberta, Edmonton Canada
Distribution: na
Date: Fri, 4 Sep 1992 18:35:42 GMT

knapp@spot.Colorado.EDU (David Knapp) writes:

>In article <dhalliwe.715546595@muskwa.ucs.ualberta.ca> userDHAL@mts.ucs.UAlberta.CA (David Halliwell) writes:

>Right, but the original poster did not metion the energy required to 
>initiate motion, which is rather important, right?

     ...but you can get all that energy back (technology limiting) when
you stop the vehicle at the new location, right?
 
     Unless the trip is an extremely short one, the energy required to
initiate motion is rather small in comparison to the energy required
to overcome friction, drag, etc. For a 2000kg car, it only takes 400kJ to
accelerate it to 20m/s. This energy would keep a 100W light bulb running
for not much more than an hour. On a one-hour car trip, the *headlights*
would use more energy than this.


Dave Halliwell
Department of Geography
University of Alberta
Edmonton, Alberta
Newsgroups: sci.chem
From: aankrom@nyx.cs.du.edu (Anthony Ankrom)
Subject: arcane rearrangement
Organization: Nyx, Public Access Unix @ U. of Denver Math/CS dept.
Date: Tue, 25 Aug 92 17:42:07 GMT

 A well-known chemist has suggested that the following rearrangement is
possible, but he failed to elaborate. (He mentioned it in passing.) I'm
curious as to how the reaction proceeds and wondered anyone out in Netland
had any idea...

   Ar-CH=CH-C-NRR'         (?)              Ar-CH2-CH-CH3
            "         --------------->             |
            O          X # steps (?)               NRR'

 In case my ascii structures are unclear, the starting product is an Aryl
substituted acrylic acid amide, the final product is an 1-Aryl-2-amino
propane. (R, R' = H)

St. Anthony

--
 If mail barfs, send it to the ip #: aankrom@130.253.192.68   

                       dAdaMatriX
      I've lost my memories to all my fears...
Newsgroups: sci.chem
From: vsummers@polaris.cv.nrao.edu (Vince Summers)
Subject: Re: the TRUTH about Methylene Chloride
Organization: National Radio Astronomy Observatory
	<1992Aug25.171443.9355@ucsu.Colorado.EDU>
	<BtMJ3q.L82@wsrcc.com>,<27AUG199208245065@phobos.ucc.umass.edu>
	<36885@uflorida.cis.ufl.edu>
Date: Wed, 2 Sep 1992 13:08:30 GMT

In article <36885@uflorida.cis.ufl.edu> dadmun@maple.circa.ufl.edu writes:
Path: cv3.cv.nrao.edu!uvaarpa!darwin.sura.net!gatech!uflorida!maple.circa.ufl.edu!DADMUN
   From: dadmun@maple.circa.ufl.edu
   Newsgroups: sci.chem
   Date: 31 Aug 92 13:14:10 GMT
   References: <1992Aug17.200337.9530@uoft02.utoledo.edu> <1992Aug25.171443.9355@ucsu.Colorado.EDU> <BtMJ3q.L82@wsrcc.com>,<27AUG199208245065@phobos.ucc.umass.edu>
   Sender: news@uflorida.cis.ufl.edu
   Reply-To: dadmun@maple.circa.ufl.edu
   Organization: University of Florida - CIRCA
   Lines: 28
   Nntp-Posting-Host: maple.circa.ufl.edu

   In article <27AUG199208245065@phobos.ucc.umass.edu>, s9874194@phobos.ucc.umass.edu (s9874194) writes:
   >In article <BtMJ3q.L82@wsrcc.com>, alison@wsrcc.com (Alison Chaiken) writes...
   >> 
   >>If you don't believe this story, try looking at the labels on some
   >>containers of hairspray in the supermarket.  Nowadays most of them
   >>say, "Does not contain methylene chloride."
[B   >> 

   That is because of the ozone layer.  Chlorinated hydrocarbons aren't good for
   it. 

   >>Alison Chaiken 				alison@wsrcc.com
   >>(510) 422-7129 [daytime] 		or chaiken@cmsgee.llnl.gov
   >>(510) 422-7300 [FAX]
   >>Live fast, die young, leave a long publication list.

  [B >I am a damned Chemist. I never wear mask or long gloves when I deal with
   >methylene chloride. I never take the lables on the bottle seriously. The
   >Daniel                                  ^
   >S9874194@uccvax.ucc.umass.edu           :
					    :
   Well then you are a fool.            --- :

   Not that MeCl is super dangerous, but not taking labels seriously is like
   hugging a 500MHz NMR magnet when u have a pacemaker.  ;^)

   Andy D.


          Methylene chloride has been the active ingredient in marine
paint remover in past years.  It irritates the skin, as I can verify
from many furniture refinishing efforts.  I never wore gloves then.
I am a chemist now, and while I have been educated carefully respecting
safety, I probably would not put gloves on now just for that either.
But which of us would allow one drop, just one drop to be placed in
each eye?
    This points out the benefit of wearing goggles.  By the way, safety
glasses are NOT protection against spills, only impact.  Studies show
safety glasses terribly ineffective against spills.  They are false
security objects.
    Lastly, I would never never advise ANYONE not to take safety 
precautions.  Saying that I don't wear them and am a chemist is an
implied endorsement of not using safety features.

Vince
vsummers@polaris.cv.nrao.edu
(don't clap, just send money)
Newsgroups: sci.chem
From: knapp@spot.Colorado.EDU (David Knapp)
Subject: Re: Luminescent Paint (Q)
Organization: University of Colorado, Boulder
Date: Sun, 30 Aug 1992 23:25:49 GMT

In article <1992Aug30.060606.195@mnemosyne.cs.du.edu> aankrom@nyx.cs.du.edu (Anthony Ankrom) writes:
>
>
> I thought ZnS used Radium to illuminate it...
>

ZnS will fluoresce  under electron bombardment (was used on CRTs) and will 
also have a steady, albeit low, constant glow after illumination by ordinary
light.

There are certainly more 'powerful' compounds for use as 'glow in the dark'
paint.  I had all this info on some xerox copies that I had lent to a friend.
She never returned them.

See?! This is why you should return borrowed materials!!!


-- 
David Knapp                                      University of Colorado, Boulder
Highly Opinionated, Aging  and                      knapp@spot.colorado.edu
Perpetual Student of Chemistry and Physics.
            Write me for an argument on your favorite subject.
Newsgroups: sci.chem,rec.scuba
From: stngiam@athena.mit.edu (Shih-Tung Ngiam)
Subject: Re: Question on partial pressure of O_2 and combustion
Organization: Massachusetts Institute of Technology
Date: Sat, 29 Aug 1992 19:55:27 GMT


> If the final mixture is safe as far as spontaneous combustion from
> hydrocarbon residues go is it safe at the point that you have pure
> O_2 at a lower partial pressure, i.e. does the nitrogen somehow
> inhibit combustion? Or is there some other mechanism at work here?
 
  Not necessarily. Yes. Maybe.

  Adding air dilutes the hydrocarbon/oxygen mixture with nitrogen.  This
makes it harder for a self-sustaining chain reaction (e.g. a fire) to
take place.  Energy that could be used to initiate hydrocarbon
oxidations essentially gets wasted heating up inert nitrogen molecules.

  At the same pressure, therefore, pure O2 would be more dangerous than
40% O2.  But your pure O2 system is at a lower pressure.  My first guess
would be that that makes the mixture less flammable. BUT the lower
pressure might make the hydrocarbons (i.e., oil and grease) more
volatile and therefore EASIER to ignite.

  Flame chemistry is quite complex.  Partial pressure is definitely not
the only factor to consider.  I would advise playing it safe.

  For the H2/O2 mixture - the reason that it does not burn is that there
is not enough oxygen to sustain the reaction.  

Shih Tung
Chem E 
Best l'il Tech School
in Cambridge
Newsgroups: sci.chem
From: rzepa@cc.ic.ac.uk (Henry Rzepa)
Subject: Re: Organic Models Kit:  How helpful?
X-UserAgent: Nuntius v1.1.1d9
X-XXMessage-ID: <A6CC30A0670450FD@macb.ch.ic.ac.uk>
Organization: Department of Chemistry, Imperial College
Date: Thu, 3 Sep 92 21:14:32 BST
X-XXDate: Thu, 3 Sep 92 21:14:08 GMT

About modelling kits, we also use them extesively, but do talk
also about the very real limitations!

As regards a program, we I use Chem3D from Cambridge Scientific.
In the latest version supporting Quicktime, it can do some cute things!
_____________________________________________
|  Dr Henry S Rzepa.                       Tel:   +44  71 225 8339 
|  Department of Chemistry           Fax:   +44 71 589 3869  
|  Imperial College                        Email: rzepa@ic.ac.uk
|  LONDON SW7 2AY
| Sent using Eudora 1.3b46.                 
_____________________________________________
Newsgroups: sci.chem
From: ANDERSONC@kcgl1.eng.ohio-state.edu (Chris Anderson)
Subject: Re: the TRUTH about Methylene Chloride
Organization: The Ohio State University
 <1992Aug28.214743.21014@hsv3.lsil.com>
Date: Sat, 29 Aug 1992 08:36:18 GMT

In article <1992Aug28.214743.21014@hsv3.lsil.com> Mike Van Pelt
(mvp@hsv3.lsil.com) writes:

>Prop. 65 also literally makes it against the
>law for anyone in a company with more than 10 employees to flush
>the toilet.  Chlorinated water reacts with organics to produce
>chloroform, which is on the list.

Not to start a flame war, but WRONG....

PROP 65 does not make it illegal for companies to flush the toilet.
Think about it:
		1)  Cities provide chlorinated water
		2)  Only emissions that cause a significant increase
			in the normal rate of cancer/birth defects
			are covered
		3)  Chloroform (CHCl3 is a reaction by-product of
			methane and water in light.  This reaction forms
			CH3Cl (80%), CH2Cl2 (10%), and a balance of
			CHCl3, CCl4, Cl3CCCl3.

Just because a chemical is on the list, does not mean that a
product containing it has to be labelled.  After all, there are very
few products that are labelled in CA!

>Who was it that said that the best way to get a bad law repealed
>was to literally and rigorously enforce it?

FYI there have only been a handful of suits that have been based
upon PROP 65.  Furthermore, Gillette, Dow, and many other companies
reformulated their products to avoid labelling.  Anytime a reduction
in the number of un-natural cancers and birth defects occurs thats
worth celebrating.  Is a few cents more precious than a human life?
--
Christopher J. Anderson
cander@sodium.mps.ohio-state.edu
andersonc@kcgl1.eng.ohio-state.edu
*
What we don't know can hurt us.
Newsgroups: sci.chem
From: aankrom@nyx.cs.du.edu (Anthony Ankrom)
Subject: acyl Cl's, amides from aldehydes
Organization: Nyx, Public Access Unix @ U. of Denver Math/CS dept.
Date: Sun, 23 Aug 92 20:18:45 GMT


 I've been wondering about the synthesis of acid chlorides and amides from
the corresponding aldehyde without having to go through several steps (i.e.
oxidation and then reaction with thionyl chloride or phosphorus chloride). 
 If oxidation is the best route then a method that will spare a double
bond is most desirable. More specifically, I am wanting to synthesize
cinnamacyl chloride and cinnamic acid amide from cinnamaldehyde (and
substituted cinnamaldehydes like 3-trifluoromethyl cinnamaldehyde).
Sparing the double bond is necessary.

St. Anthony  


--
 If mail barfs, send it to the ip #: aankrom@130.253.192.68   

                       dAdaMatriX
      I've lost my memories to all my fears...
From: cec35848@uxa.cso.uiuc.edu (Chuck Carroll)
Subject: Re: Carburetors, gasoline, and why I don't recycle
Organization: University of Illinois at Urbana
Distribution: na
Date: Thu, 3 Sep 1992 00:27:25 GMT

joec@fid.morgan.com (Joe Collins) writes:

>>In article <1992Sep02.010828.24870@rs6000.cmp.ilstu.edu> ejhupper@rs6000.cmp.ilstu.edu (Eric Huppertz) writes:

>Eric writes a long article about how the oil companies et al have 
>discovered a way to get excellent miles per gallon but won't release
>it for sale since the price of oil/gasoline would plummet. Thus, they
>keep the technique locked up in a vault and thus have been screwing
>the customer all these years.

>It should be fairly to prove/disprove this, emperically.

>Simply put, look up the potential energy in a gallon of automotive
>gasoline. Factor in inefficiencies due to friction, heat loss and so forth.
>The resultant energy is available to move a vehicle a distance of X miles.
>BTW- I would guess a car is less than 20% efficient. Even electrical
>companies are only 40-50% efficient, with the rest lost to friction (motor
>bearings, fluid flow), heat loss (steam, etc), electrical resistance 
>in the transmission lines.

1)  You'll need a pretty good estimate of friction, since without it
it would take no energy to move a car over level ground.  Perhaps
this can be estimated by the distance it takes a car to roll to a stop?

2)  Don't forget energy lost due to incomplete combustion.

-- 
Chuck Carroll		  | "What can I say when I've ruined your day
cec35848@uxa.cso.uiuc.edu |  And made you all angry and surly?
			  |  How could I make such a thoughtless mistake
			  |  And bury your mother too early?" -- Earl Sinclair
Xref: sparky sci.chem:3282 rec.scuba:4744
From: vsummers@polaris.cv.nrao.edu (Vince Summers)
Subject: lab safety records
Organization: National Radio Astronomy Observatory
Distribution: sci.chem
Date: Thu, 3 Sep 1992 13:17:28 GMT

     Any accidents should be reported to the safety officer .  When (hopefully
if) OSHA comes, they want to see your accident records.  If you say, Well,
we have had none in years!, you're in trouble.
     Incidentally, where I work, our safety officer has NO chemical background.
I am primarily responsible, being the chemist, the only chemist, and hence
have recently been placed in charge officially as the CHEMICAL safety person.

Vince
vsummers@polaris.cv.nrao.edu
From: toms@fcs260c2.ncifcrf.gov (Tom Schneider)
Newsgroups: sci.chem
Subject: Re: Entropy of the Universe, (was Re: Genesis - fact or fiction)
Date: 26 Aug 92 02:57:12 GMT
Organization: Frederick Cancer Research and Development Center

In article <1992Aug25.205224.4519@cs.rochester.edu> dietz@cs.rochester.edu
(Paul Dietz) lists the problems with the formation of an RNA world.

At least the RNA world proposal puts us to a simpler picture.  Maybe there will
be another discovery that points the way back further, or maybe this is a false
start.  In any case, we seem to have gotten around a really big chicken-egg
paradox by using that idea.  I'm wondering what the next step will be.  Maybe
you can see a clue in all the problems you listed.

  Tom Schneider
  National Cancer Institute
  Laboratory of Mathematical Biology
  Frederick, Maryland  21702-1201
  toms@ncifcrf.gov
Newsgroups: sci.chem
Subject: STN Express Usage?
From: R.Singh@massey.ac.nz (R. Singh)
Date: Sun, 23 Aug 92 22:50:27 GMT
Organization: Massey University
Keywords: STN Express, telnet, chemistry abstracts
X-Newsreader: Tin 1.1 PL4

Has anybody used STN Express over telnet rather than using a modem?


Is it possible?

Raminder Singh


Newsgroups: sci.chem
From: tony2@prefect.uucp (21131-gozdz)
Subject: Re: Viton decomposition
Organization: Bellcore, Livingston, NJ
Date: Tue, 25 Aug 92 20:36:07 GMT

In article <r=my6dk@rpi.edu> waitsc@rpi.edu writes:
>Keywords: VitonA, VitonB, Fire, Chemical Decomposition
>
>There is a memo floating around from a fire department noting that
>Viton decomposes under fire conditions into a substance that
>continues to eat into your hands and exposed body parts until "the
>only way to stop it is amputation." I am sure that this is hysteria.
>To the best of my knowledge, Viton is a substance that may decompose
>into a sticky mass containing hydrogen fluoride. As such it is indeed
>a dangerous substance in a fire - It is used in automobiles and trucks
>as gasket material or something like that.
>
>Does anyone have information about Viton and its thermal decomposition?
>
>Sam Wait
>Rensselaer Polytechnic Institute
>waitsc@rpi.edu
>Troy, New York

Viton(tm) is a series of fluorinated elastomers from
DuPont. They are copolymers of vinylidene fluoride
(CH2=CF2) with hexafluoropropene (CF2=CF-CF3), but some
contain tetrafluoroethene (CF2=CF2) to increase their
solvent resistance, or perfluorovinyl methyl ether
(CF2=CF-O-CF3) to improve their low-temp elasticity.

According to Polymer Handbook (3rd ed., p. II/372) and
Heat Resistant Polymers (Critchley et al. Plenum, 1986
p. 100-103 (Thermal Stability), such copolymers start
to decompose at > 350 C in air. If such copolymers
contain hydrogen, in this case in the form of -CH2-CF2-
units, they will always produce a substantial amount of
gaseous HF on heating at ~400 C. And don't take it
lightly; dry, gaseous HF is a _very_ nasty stuff. It
causes necrosis etc, thus your comment about amputation
is relevant.

A friend of mine exposed his fingernail to a whiff of
dry HF when unscrewing a pressure regulator from a
lecture bottle containing HF. The result: a horrible,
long-lasting pain, a lost fingernail, and a long
healing process.

Let's not underestimate the effects of dry HF that
could evolve when Viton is thermally decomposed under
any conditions.

Tony

-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
Antoni S. Gozdz                tel  (908) 758-2931  |  Bellcore  NVC 3X-261
tony2@prefect.cc.bellcore.com  FAX  (908) 741-2891  |  Red Bank, NJ 07701, USA
-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
From: brueck@inm.uni-sb.de (Stefan Brueck)
Newsgroups: sci.chem
Subject: Re: Luminescent Paint (Q)
Date: 2 Sep 92 10:09:11 GMT
Organization: Institute for New Materials (INM), Saarbr"ucken, Germany.

Revell a manufactor of plastic aircraft models has such a luminescent paint.
the paint can be diluted with water too. 

ciao
stefan
Newsgroups: sci.chem
From: pkrause@triton.unm.edu (Paul Krause CIRT)
Subject: Merck Index
Date: Wed, 26 Aug 92 04:16:32 GMT
Organization: University of New Mexico, Albuquerque NM
Summary: looking for one


I would like to know of an address which i could send an inquiry to as to buyinga Merck Index.  I was hoping that one of you could e-mail me, or post the
publisher's address.  A science teacher at my son's school would like one, as 
the school doesn't have one currently.  I do have one, but I am not totally
sure that the address in it for the general direction for the publisher is 
correct anymore (it is a 7th edition).
Thanks.
Paul
pkrause@triton.unm.edu
From: m0102@tnc.UUCP (FRANK NEY)
Newsgroups: sci.chem
Subject: Proper alloy combinations for specie
Date: 27 Aug 92 11:04:32 GMT
Reply-To: m0102@tnc.UUCP (FRANK NEY)
Organization: The Next Challenge, Fairfax, Va.


I need some information for a novel I am writing, and I've been having
trouble dealing with that big green monstrosity masquerading as a
physics and chemistry reference.

Which metals are most useful with gold and silver for making coins,
and in what proportions?  What is the best compromise between ease of
manufacture, durability and use?

A quick and dirty answer with a pointer towards suggested references
is acceptable.

Thanks in advance,
Frank Ney N4ZHG EMT-P  LPVa NRA ILA GOA CCRTKBA "M-O-U-S-E"
Commandant and Acting President, Northern Virginia Free Militia
Send e-mail for an application and more information
----------------------------------------------------------------
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-- 
The Next Challenge - Public Access Unix in Northern Va. - Washington D.C.
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Xref: sparky sci.chem:3322 rec.scuba:4796