HDTenEightyP/NetNews huggingface dataset:
From: jeff@kuhub.cc.ukans.edu (Jeff Bangert)
Newsgroups: sci.chem
Subject: Non-linear Regression in Chemistry
Date: 3 Sep 92 06:44:00 CDT
Organization: University of Kansas Academic Computing Services

A chemist has asked me to solve a problem: she has data and a model
which is to be fit by 'least squares'.  It looks like non-linear
regression, except that:

    1. the model has two equations
    2. both are non-linear
    3. there are parameters common to the two equations.

I would like to know:

    1. is there a 'standard' method for solving this problem?
    2. is there literature in stat or chemistry which I could read?

Clearly, I can form the sum of squared errors for each equation and
add them together.  I have lots of methods for minimizing the result.
However, this seems to ignore the question of the weighting of the two
equations.

I solved this kind of problem several years ago by writing FORTRAN +
IMSL.  Now that it has come up again, I wish I had some backup
literature that at least suggests the 'standard' solution method.  I
don't like reinventing the wheel.

Since the current data matrix is small, 4 by 2, I'm going to use
non-linear optimization in Quattro Pro this time.  It produces nice
graphs.  But, if I stick with QP, I'll also have to calculate the
standard errors of the parameter estimates.  Right now, I'm not
looking forward to this.

Thanks for the help,
-- 
Jeff Bangert			jeff@kuhub.cc.ukans.edu
Computer Center			jeff@ukanvax.bitnet
University of Kansas
Lawrence, KS 66045
(913)864-0466
Newsgroups: sci.chem
From: nowsa%Solomon.Technet.sg (shan wong)
Subject: sci.chem
Organization: National University of Singapore
X-Newsreader: Tin 1.1 PL5
Date: Thu, 3 Sep 1992 01:23:50 GMT
From: ucca245@ucl.ac.uk (Andrea Sella)
Newsgroups: sci.chem
Subject: Luminescent Paint (Q)
Date: 26 Aug 92 17:06:00 GMT
Organization: Bloomsbury Computing Consortium

A student from a local art college has asked me for advice on how to 
"make" luminescent paint. By luminscent he means glow in the dark.
he claims not to be able to find any commercially.
Any ideas about what one might add to a water-based emulsion to get
such a material. 

Ideas involving radium will not be favourably received (:))

Send replies direct to me, if you want, and I will summarize to the
net.

Andrea Sella
UCL Chemistry
aka ucca245@ucl.ac.uk
Newsgroups: sci.chem
From: James Petts <pettsj@visigoth.demon.co.uk>
Subject: Re: Organic Models Kit:  How helpful?
Organization: No Affiliation
Date: Tue, 1 Sep 1992 06:50:18 GMT
X-Useragent: Nuntius v1.1



In article <1992Aug29.192335.5440@col.hp.com> Chris Magnuson,
chrism@col.hp.com writes:
>  How helpful are the plastic beads model kits for learning organic
chemistry?
>Would computer modeling programs be better?  If so, can someone
recommend one
>for the Mac?

I am a full-time molecular modeller, and the first thing I did when 
taking up my new appointment where I work now was to purchase some 
plastic models (the Darling models from Aldrich). You cannot really do 
without them IMHO.

As far as modelling packages for the Mac go, I would stronlgy suggest 
Alchemy from:

Tripos Associates
1699 S. Hanley Road, Suite 303
St Louis
MO 63144-2913
(314) 647 1099

James Petts

********************************************************************
* "We use the classical theory on Mondays, Wednesdays and Fridays, *   
*  and the quantum theory on Tuesdays, Thursdays and Saturdays."   *
************************************** Wm. Bragg *******************
From: jprovo@Gnu.ai.mit.edu (The Wandering Pedestal of Angst)
Newsgroups: sci.chem
Subject: Merck Index
Summary: anywhere electronic?
Date: 2 Sep 92 03:01:46 GMT
Organization: Russell Street UN*X Consultations
X-Subliminal: you will send me email....you WILLL send me email...

Title &Summary say it all....

...even a -sigh- commercial source would be appreciated.

Please reply via email as I'm not a chemist, nor do I play one in USENet.
This is a question for an associate....

Thanks,
Joe Provo

-- 
Disclaimer: "I'm the only one foolish enough to claim these opinions as mine."
jprovo@gnu.ai.mit.edu                                       jzp@gene.ummed.edu
    Russell Street UN*X Consultations and Development     (NIC handle: JZP)
                            Rev. Dkr. Nick LaRG0, ASC
From: ladasky@netcom.com (John J. Ladasky II)
Newsgroups: sci.chem
Subject: Azide Chemistry
Date: 27 Aug 92 16:54:45 GMT
Organization: Netcom - Online Communication Services (408 241-9760 guest)


	O.K., I've got an o-chem question.

	The paper, "Selective covalent binging of an Ethidium Analog to
Mitochondial DNA with Production of Petite Mutants in Yeast by Photoaffin-
ity Labeling" (Hixon SC et. al., J. Mol. Biol 92:319-329 [1975]), contains
a reference to a reaction that is not covered in my o-chem references.

	A primary amine (alpha to a benzene ring, if that matters) is
converted to an azide by suspension of the reactant in concentrated HCl 
and sodium azide at 5C, followed by dropwise addition of sodium nitrite.
Does anyone know of a general refernce to this reaction?  In particular, 
I'm interested to know what side reactions might occur - will the azide 
attack alkylated tertiary amines?

	Thanks in advance.

-- 
=============================================================================
 John J. Ladasky II ("ii")				(ladasky@netcom.COM)
-----------------------------------------------------------------------------
"Great composers do not borrow - they steal."  - John Ladasky		~ -	
(At the urging of fellow netter Lon Amerman, I stole the above		o o
 quote from Igor Stravinsky, who stole it from a statement made		 >
 by Pablo Picasso about painting, who stole it from...)			\_/
-----------------------------------------------------------------------------
"Talking about music is like dancing about architecture." - Elvis Costello?
							    Frank Zappa?
"Property is theft." - Groucho				    Laurie Anderson?
=============================================================================
Newsgroups: sci.chem
From: dthurlow@vax.clarku.edu
Subject: Chem tutorials for the Mac
Organization: Clark University
Date: 27 AUG 92 21:07:03 GMT

Could someone please direct me to access to chemistry tutorials
for the macintosh?  I've tried archive.umich.edu, but so far
have been unsuccessful at ftp'ing any files. Thanks.
From: dadmun@maple.circa.ufl.edu
Newsgroups: sci.chem
Subject: clean glass ashtray sudenly breaks...
Date: 28 Aug 92 14:50:27 GMT
Reply-To: dadmun@maple.circa.ufl.edu
Organization: University of Florida - CIRCA

One reason a clean glass ashtray could suddenly break is that its
potential energy could suddenly be converted into kinetic energy for
reasons such as a cat knocking it off a table, or dropping out of a
second story window, etc.  Another could be someone dissatisfied with 
the quality or disposition or the ashtray or even the cleanliness of
it - and suddenly smashing it to bits with a hammer.  Perhaps the
ashtray itself felt low self-esteem from its lack of butts contained
within and was able to break itself in some kind of suicide.  

I couldn't resist - I've been reading too much Douglas Adams lately.

"The herbivores ate well 'cause their food didn't never run."
                                       -Jon Fishman of Phish

Andy D.
From: nuke@reed.edu (Bill Newcomb)
Newsgroups: sci.chem
Subject: Re: the TRUTH about Methylene Chloride
Date: 2 Sep 92 16:54:40 GMT
Article-I.D.: reed.1992Sep2.165440.779
Organization: Reed College, Portland, OR

In article <36885@uflorida.cis.ufl.edu> dadmun@maple.circa.ufl.edu writes:

>Not that MeCl is super dangerous, but not taking labels seriously is like
          ^^^^
WE are not alking about methyl chloride, which is what most organic chemists
(and at least one physical chemist;-) would infer from this abbreviation. If
you want to abbreviate methylene chloride, then write it CH2Cl2 or MeCl2 or
even DCM (dichloromethane). Similarly, chloroform is CHCl3 or, less
commonly, MeCl3. Carbon tet is carbon tet. 

Sorry to get so obnoxious, but I kept getting confused earlier when I didn't
read news every day and couldn't tell which one people were talking about.

nuke "the pedant" @reed.edu
--
~/.oo
Newsgroups: sci.chem,comp.text.tex
From: bwildasi@silver.ucs.indiana.edu (Ben Wildasin)
Subject: Request for comments: computerized chemical structure drawing
Keywords: TeX, chemistry, computers, typesetting, formulas
Organization: Indiana University
Date: Mon, 31 Aug 1992 14:35:17 GMT


I am developing a chemical structure-drawing macro package for plain TeX
(not LaTeX, although it might be compatible). This survey is
intended to gauge the level of interest in such a package and the
features that potential users would like to see included.

ChemTeX has been praised on the net. What features make it particularly
attractive? What about it would you change? If you don't use TeX, or use
TeX in conjunction with a graphical-interface formula generator, would you
be willing to switch to a text-based system for improved typographic
quality? What features would be important in a structure-drawing program
(TeX-based or otherwise?)

I appreciate your answers to any of these questions as well as any other
comments on the topic. I will also e-mail to anyone interested a PostScript
demo file containing some examples of structures I have drawn using my
macros.

Thanks very much.
-- 
Ben Wildasin                           bwildasi@silver.ucs.indiana.edu

"...it may be said of men in general, that they are ingrates, fickle,
 deceivers, evaders of danger, desirous of gain." --Machiavelli
Newsgroups: sci.chem
From: rzepa@cc.ic.ac.uk (Henry Rzepa)
Subject: Re: MOPAC bug and sources of source code
X-UserAgent: Nuntius v1.1.1d9
X-XXMessage-ID: <A6CC2DF0C70150FD@macb.ch.ic.ac.uk>
Organization: Department of Chemistry, Imperial College
Date: Thu, 3 Sep 92 21:03:05 BST
X-XXDate: Thu, 3 Sep 92 21:02:40 GMT

In article <1992Aug30.164937.9780@uoft02.utoledo.edu> ,
dsmith@uoft02.utoledo.edu writes:
>has ever gotten "official permission" (if there is such a thing) to

I endorse everything above. I have become most concerned at the
proliferation
of versions. All bugs should be reported to Jimmy Stewart, who maintains
the official version.

PS MOPAC 7 coming some time in the next few months!
_____________________________________________
|  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: vsummers@polaris.cv.nrao.edu (Vince Summers)
Subject: Chemical Safety
Organization: National Radio Astronomy Observatory
Distribution: sci.chem
Date: Fri, 28 Aug 1992 19:52:51 GMT

     About a year and a half ago my employer, NRAO, sent me to Chicago to
take a course in safety.  Since my BS was achieved in the early 70's, it
should be obvious safety wasn't taught as a course in school.
     I found out at the course (given by Nat'l. Safety Council) that
when only one person with chemical background is employed for a firm, he 
is AUTOMATICALLY RESPONSIBLE--LIABLE--for the chemical safety of his site.
Blew my mind.  I did not desire responsibility.  I thought the employer was
responsible.  What do you think of that?  Are you in a similar boat?
Did you know YOU are responsible?

Vince
vsummers@polaris.cv.nrao.edu
From: moody@brahms.udel.edu (John David Moody)
Newsgroups: sci.chem
Subject: Re:  gold test
Date: 28 Aug 92 15:02:35 GMT
Organization: University of Delaware

If I remember correctly, a streak test for minerals (marking a white tile with
a mineral and noticing the color of the streak) should help differentiate
whether it is real gold or fools gold.  Real gold leaves a gold streak, whereas
fool's gold leaves a brownish streak.

If unable to perform the streak test, adding nitric acid to the gold may
help differentiate.  Fools gold (iron pyrite) reacts with nitric acid to
give off a brown gas.  Gold does not react with nitric acid.

I'm not fully sure of this, but I hope this helps

-  John David Moody
From: fred@network.ucsd.edu (Fred Criscuolo)
Newsgroups: sci.chem
Subject: CSD to PDB Converter Wanted
Keywords: CSD, PDB
Date: 3 Sep 92 23:46:47 GMT
Organization: University of California, San Diego
NNTP-Posting-Host: network.ucsd.edu

I am looking for software to convert Cambridge Scientific Database FDAT file
entries to PDB format.  I realize that this function can be performed by
some existing packages such as Polaris.  I need a separate program.
Thanks in advance


Fred Criscuolo
Chemistry & Biochemistry Dept                 (619) 546-4083 (voice)
Gensia Phramaceuticals
fcriscuo@ucsd.edu                             (619) 546-4516 (fax)                  

         \ \ \ \ .    There's more to life than rowing..    ./ / / /      
          / / / /       but not much !!!                      \ \ \ \
From: eliseeva@ohstpy.mps.ohio-state.edu
Newsgroups: sci.chem
Subject: ACS e-mail address? Help, please.
Date: 3 Sep 92 16:14:22 GMT
Article-I.D.: ohstpy.13633.2aa6019e

Does anybody know weather there is e-mail network for American Chemical
Society? I know such one exists for Math sciences. I think there must be some
electronic information about recent publications in different areas of
chemistry, schedule of conferences and employment possibilities.

Thanks in advance for help. Please, contact Maria at
"eliseeva@ohstpy.mps.ohio-state.edu"
From: dadmun@maple.circa.ufl.edu
Newsgroups: sci.chem
Subject: Methylene Chloride
Date: 30 Aug 92 05:19:57 GMT
Reply-To: dadmun@maple.circa.ufl.edu
Organization: University of Florida - CIRCA

Back to the original concern of the husband and wife, and the drum of CH3Cl
in the ocean.  How did it get there?  MeCl may not be very hazardous, but
do we want it (or other more nasty things) floating around in the lifesource
of the planet?  We can debate this issue to death - as we have proven here,
but who is doing anything about it?  A very small percentage.  We should take
action to prevent careless dumping in our oceans - or anywhere.  I must admit
that I have been somewhat concerned about MeCl since my undergrad experience.
During my final semester, I used it a lot as a solvent for UV-Vis spectroscopy
and washing NaCl plates, etc.  If your a chemist, you use the stuff.  It 
says right on the bottle that it is a liver toxin and suspect carcinogen.
Nonetheless, it always seemed more of a hassle to me to protect myself with
gloves than to spill a little filling cuvettes.  It evaporates so quickly
that usually all you feel is a cold hand.  Well, everyday exposure is not 
needed by me.  Who cares if it is not THAT bad.  The fact is that it should
not be taken as no threat at all - and I am not just talking about MeCl.  Do
you think that just because the ocean is SO BIG and the garbage so little that
it doesn't matter - It Does, and it will more and more if it slides.  What
if a nice tuna happened to get a localized spill and you ate it.  YUM.  So,
I am not so concerned about the MeCl on the beach as I am about the fact that
anything is on the beach in a 55gal drum.  Look at how much damage we humans
have done in 100 years.  Well that's industrialization for ya.  Not that I
am against it.  We just have a growing lack of moral responsibility.  As  
technology increases our need for human interface decrease and we become more
egocentric.  Let's look out for each other.
Please reply here or directly if you feel so inclined.
Andy 
Dadmun@ufcc.ufl.edu
Xref: sparky sci.chem:3352 rec.autos:21274 rec.autos.tech:12100 misc.consumers:16003 sci.environment:10993 talk.environment:3515
From: dhepner@cup.hp.com (Dan Hepner)
Newsgroups: sci.chem,rec.autos,rec.autos.tech,misc.consumers,sci.environment,talk.environment
Subject: Re: Carburetors, gasoline, and why I don't recycle
Date: 2 Sep 92 21:03:02 GMT
Distribution: na
Organization: Hewlett-Packard, Cupertino, CA


 
>  You know as well as I do where they are:  In the
> vaults of the world's major oil companies.

> The above is (c)1992 by Eric J. Huppertz.  

One imagines a kid at the zoo throwing a housecat into the wolf 
pack, sitting back and watching the fun.  This is a classic; 
something that _everyone_ can respond to.  No doubt some jokster 
has archived this along with his copy of Craig Shergold's passionate 
appeal for business cards, and will post them randomly to hook the 
newcomers.

Dan Hepner
Newsgroups: sci.chem
From: slawek@aries.scs.uiuc.edu (Slawomir Z. Janicki)
Subject: MOPAC
Summary: Missing SIZES file
Organization: University of Illinois at Urbana
Date: Mon, 31 Aug 1992 04:23:03 GMT
Keywords: MOPAC, SIZES

The SIZES file is apparently missing in my version of MOPAC (NOT a QCPE version)
The description in the manual is not sufficient to restore it. Could somebody
e-mail me a default vesion of SIZES?
Thanks in advance.

Slawek Janicki
Slawek@m.scs.uiuc.edu

P.S. I have a similar problem with AMPAC (also a missing SIZES file).

P.P.S. Is there a ready-to-use version of MOPAC for Silicon Graphics Iris-4D?
Newsgroups: sci.chem
From: aankrom@nyx.cs.du.edu (Anthony Ankrom)
Subject: Re: arcane rearrangement
X-Disclaimer: Nyx is a public access Unix system run by the University
	of Denver for the Denver community.  The University has neither
	control over nor responsibility for the opinions of users.
Organization: Nyx, Public Access Unix at U. of Denver Math/CS dept.
Date: Sun, 30 Aug 92 06:02:24 GMT

In article <1992Aug27.195914.37593@ux1.cts.eiu.edu> cfthb@ux1.cts.eiu.edu
(Howard Black) writes:
>In article <1992Aug25.174207.20706@mnemosyne.cs.du.edu> aankrom@nyx.cs.d
.edu (Anthony Ankrom) writes:
>> 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 Netl
nd
>>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 Ar
l
>>substituted acrylic acid amide, the final product is an 1-Aryl-2-amino
>>propane. (R, R' = H)
>
>    Your ascii structures are very clear....the structure of amphetamine
is
>hard to miss.  Perhaps the DEA can help you.
>
>-- 
>   ******************************************************************
>     Howard Black                             cfthb@ux1.cts.eiu.edu
>     Department of Chemistry                  Eastern Illinois Univ. 


 I
 It's not illegal to seek knowledge about the chemistry of drugs. I happen
to have a great interest in pharmacology, and part of that interest just
happens to be in the area of psychedelic amphetamines. So sue me...
I've never taken one. The chemistry just interests me. Some people seem
very interested in explosives which are far more deadly than any drug.
Imposing morality on the quest for knowledge impedes the function of the
net in my opinion. If you don't want to answer my questions, then don't
and come up with a decent flame. If you're going to flame me you'd better
roast me good.
 Someone should have some idea about the reaction mechanism at hand here.
It simply intrigues me. If I were interested in the illicit manufacture of
amphetamines, it should be clear to anybody that this would not be a very
economical way to go about it. 
 I already know several methods of preparing methamphetamine. Big deal.

 Benzaldehyde and nitroethane and reduction

 reductive amination of phenylacetone

 reduction of ephedrine with Na

 (These all yield amphetamine and not methamphetamine, but the same
reactions cxan be applied...)

 I certainly hope that this group doesn't continue to be so philistine.
If my interest in pharmacological chemistry is so deviant then turn on the
broiler...

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: rzepa@cc.ic.ac.uk (Henry Rzepa)
Subject: Re: chemistry ftp sites
X-UserAgent: Nuntius v1.1.1d9
X-XXMessage-ID: <A6CC2FEA980350FD@macb.ch.ic.ac.uk>
Organization: Department of Chemistry, Imperial College
Date: Thu, 3 Sep 92 21:11:30 BST
X-XXDate: Thu, 3 Sep 92 21:11:06 GMT

How about kekule.osc.edu and MacSciTech (128.60.0.21)
for chemistry programs. See also comments about MOPAC
and oakland!
_____________________________________________
|  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,rec.autos,rec.autos.tech,misc.consumers,sci.environment,talk.environment
From: brooks@mcnc.org (Ted Brooks)
Subject: Re: Carburetors, gasoline, and why I don't recycle
Organization: MCNC Center for Microelectronics, RTP, NC
Distribution: na
Date: Thu, 3 Sep 1992 21:00:47 GMT

In article <dhalliwe.715546595@muskwa.ucs.ualberta.ca> userDHAL@mts.ucs.UAlberta.CA (David Halliwell) writes:
>knapp@spot.Colorado.EDU (David Knapp) writes:
>
>>In article <Btz7xq.H47@news.cso.uiuc.edu> cec35848@uxa.cso.uiuc.edu (Chuck Carroll) writes:
>>>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. 
>
>
>>What about W=F*d?  Ek=1/2m*(dV)^2?  P=m(dV)?
>
>   What about "An object in uniform motion will continue in uniform motion 
>unless acted upon by a force"? The only energy required would be that used

Yeah, but you still have to satisy F=M*A and Ek=1/2*m*v**2 to get the car
moving in the first place.
From: vsummers@polaris.cv.nrao.edu (Vince Summers)
Newsgroups: sci.chem
Subject: Re: Entropy of the Universe, (was Re: Genesis - fact or fiction)
Date: 27 Aug 92 13:18:01 GMT
	<1992Aug25.205224.4519@cs.rochester.edu> <3765@fcs280s.ncifcrf.gov>
Organization: National Radio Astronomy Observatory

In article <3765@fcs280s.ncifcrf.gov> toms@fcs260c2.ncifcrf.gov (Tom Schneider) writes:
Path: cv3.cv.nrao.edu!uvaarpa!caen!uunet!haven.umd.edu!mimsy!lhc!ncifcrf!fcs260c2!toms
   From: toms@fcs260c2.ncifcrf.gov (Tom Schneider)
   Newsgroups: sci.chem
   Date: 26 Aug 92 02:57:12 GMT
   References: <VSUMMERS.92Aug24124956@polaris.cv.nrao.edu> <3759@fcs280s.ncifcrf.gov> <1992Aug25.205224.4519@cs.rochester.edu>
   Sender: news@ncifcrf.gov
   Organization: Frederick Cancer Research and Development Center
   Lines: 14

   In article <1992Aug25.205224.4519@cs.rochester.edu> dietz@cs.rochester.edu
[B   (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.

[B     Tom Schneider
     National Cancer Institute
     Laboratory of Mathematical Biology
     Frederick, Maryland  21702-1201
     toms@ncifcrf.gov
Creation teaches the chicken before the egg.
Vince
vsummers@polaris.cv.nrao.edu
Newsgroups: sci.chem