HDTenEightyP/NetNews huggingface dataset:
From: winalski@adserv.enet.dec.com (Paul S. Winalski)
Subject: Re: Left-handed sugar
Reply-To: winalski@adserv.enet.dec.com (Paul S. Winalski)
Organization: Digital Equipment Corporation, Nashua NH
Date: Wed, 30 Dec 1992 23:33:12 GMT


In article <dexter.725655833@aries>,
dexter@aries.scs.uiuc.edu (The Gecko) writes:
|>
|>	Unlike you, I would expect the specificity of these enzymes to be more
|>or less absolute.  Glycolysis is such a central and finely tuned pathway that 
|>I would anticipate stereochemical control of substrate choice to be essential.
|>If you look more closely, you will find that the essential oxidative chemistry
|>in glycolysis happens *after* splitting of fructose-1,6-bisphosphate to G-3-P
|>and DHAP and involves oxidation at what were the central carbons of glucose.
|>But here again, the enzymes are specific for a particular sugar enantiomer.
|>I don't know of any examples of these enzymes acting on epimers or analogs 
|>of the normal substrates, including D/L isomers.  I certainly know of examples 
|>of *inhibition* by analogs.  

According to my copy of Lehninger (regrettably quite old), the enzyme that
catalyzes the reaction fructose-1,6-diphosphate <-> DHAP + G-3-P (aldolase?)
is absolutely specific for dihydroxyactone phosphate, but will accept a
variety of aldehyde phosphates, or aldoses, in place of G-3-P.  It will take
glyceraldehyde as well as its 3-phosphate, for example, to give
fructose-1-phosphate.  This means that for aldolase, at least, the configuration
about carbon 3 of the aldehyde substrate isn't a critical factor.  It very
well might be that a D-configuration about this carbon is critical, however.
That's why I asked the question whether D/L specificity had been studied
for these enzymes (and the related ones of the Calvin cycle and pentose
phosphate shunt).

It does seem likely, though, that any path that exists would likely be
convoluted, slow, incomplete, or all three, and therefore L-glucose would be
at best a far less useful source of energy than D-glucose.  Which answers the
question that originally triggered this thread, namely, could L-sugars be used
as a non-nutritional sweetener?  The answer to the non-nutritional part seems
to be yes.

--PSW
Newsgroups: sci.chem
From: saj@chinet.chi.il.us (Stephen Jacobs)
Subject: Re: Benzene in Strawberries?
Summary: I has to be there
Organization: Chinet - Public Access UNIX
Date: Tue, 22 Dec 1992 04:49:52 GMT

In article <BzMtIt.J86@oryx.com> xslkkk@oryx.com (kenneth k konvicka) writes:
>Any of you aromatic types know of benzene (in low ppb concs) produced in fruit,
>vegetables, or anything else we might inhale or ingest?  Refs?
>
> 

Every time I'm forced to analyze a food product for benzene for regulatory
reasons, I threaten to measure it in organically grown carrots, too.  Benzene
is easy to measure down to 0.1 ppb, and another factor of 30 shouldn't make
anyone break a sweat.  Ultimately, you could probably get down to single 
molecules with microwave.  And after all, it's a local energy minimum for the
C:H::1:1 system, so things turn into benzene.  A particular instance that 
applies in fruits: benzaldehyde is a common component of fruit aromas.
Benzaldehyde oxidizes to benzoic acid in air.  Benzoic acid is decarboxylated
in the presence of free radicals (for instance, those generated in the course
of benzaldehyde oxidation...).  This is aside from the general benzene
background (just possibly associated with motor fuels).

So in general, benzene is everywhere if you look hard enough.  There are
innumerable publications on 'volatile compounds of <any odorous material
you can think of, and many you can't>'.  If the laundry lists go to low
enough molecular weight, benzene will usually be on them.  If you really
need some specific references, email me.

                                           Steve     saj@chinet.chi.il.us
From: Harald_Ziebarth@k.maus.de (Harald Ziebarth)
Newsgroups: sci.chem
Subject: Re: Left-handed sugar
Date: Mon, 28 Dec 92 17:58:00 GMT
Organization: MausNet (Mitglied im IN e.V.)
X-Gateway: MausGate/News 1.14D/hb

m>Name: Mark Robert Thorson
m>Box : The Portal System (TM)
m>Von : mmm@cup.portal.com (So, 27.12.92 09:17)

m>Please excuse the cross-posting into the sci newsgroups, but we've been
m>having a discussion in rec.food.cooking about the supposed existence
m>of left-handed sugars which are indigestible hence calorie-free.
m>I contend that if L-sugars were calorie-free, they probably wouldn't
m>be sweet, either.  Can someone in the sci groups clarify this?

In 1981 the Biospheric Incorporated, an environmental and health sciences'
firm in Rockville (Maryland), got a patent for "left-handed" sugars (s. [2]).
This product, named "Lev-O-Cal", is sweet as sugar, but have no calories,
because the organism  -microorganisms (no caries !) and humans-  can't
utilize this form of chemical energy.

The patent specification include reference to synthesis and literature.

[1] Szarek, W.A.; Jones, J.K.N. (Queen's University at Kingston, Kanada):
    "L-Sucrose und Verfahren zu deren Herstellung"
    Deutsches Patentamt, Offenlegungsschrift 28 16 268

[2] Levin, G.V. (Biospherics Incorporated, Rockville, Md.):
    United States Patent 4,262,032

---------------------------------------------------------------------------
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Newsgroups: sci.chem,sci.environment
From: jgd@dixie.com (John De Armond)
Subject: Re: Alternative refrigerants
Date: Wed, 23 Dec 92 21:52:34 GMT
Organization: Dixie Communications Public Access.  The Mouth of the South.

ahgrabow@apgea.army.mil (Alexander H. Grabowski <ahgrabow>) writes:

>From what I heard I understand that the acute toxicity as well as the 
>subacute long-term toxicity is too high to allow HFC-134a to be used 
>in industrial processes.

Probably true.  Still to be determined.  The PAG-based oil is also nasty.

>If anybody has different information on that, I really would be happy
>to hear more about it.

DuPont has a sorta-replacement for R-12 on the market called SUVA MP-52.
It is not a drop-in because the oils are not compatable.  System 
flushing is required.

George Goble, ghg@ecn.purdue.edu, who has posted in this thread and
is too bashful to blow his own horn, has developed and patented a 
drop-in, 100% compatable, non-flammable replacement for R-12.  His product, 
called "GHG R-12 substitute", abbreviated by me to GHG-12, is compatible
with R-12, can be mixed with R-12 in any proportion and increases the
cooling capacity of the target system from about 20 to 60%.  It has
an ODP factor of 0.05 and is on EPA's "tentative OK" list.  

I have been involved in this project as a tester and a cheer leader for
a couple of years.  GHG-12 is successfully been running in several
hundred vehicles.  There have been only 2 or 3 "failures", only one
of which is attributed to the refrigerant.  This was on one of my
systems where an O-ring blew out after installation.  The system in
question is over 20 years old and contained a replacement O-ring of
unknown vintage and parentage so the blame does not really belong on
the refrigerant.

A detailed technical article on GHG-12 appears in the free sample edition
of my magazine _Performance Engineering_ (TM).  It is available free for
the asking by mailing your postal address to perform@dixie.com.  Do
NOT mail to me at jgd@dixie.com asking for samples.  My staff handles
the requests; I dump 'em.

The patent is #5,151,207.  George can also be contacted for more 
information.  GHG-12 and/or a self-sealing version that plugs hose
porosities and small leaks can be orderd from 

Monroe Air Tech
800 424 3836
522 West Second St.
Bloomington, IN 47403
812 332 2284 (fax)

John

Claimer: I'm intimately involved in the project and think GHG-12 is
the neatest stuff since sliced bread.  Apparently so do a lot of other
folks, judging by the testamonials I'm receiving here at the mag.
-- 
John De Armond, WD4OQC               |Interested in high performance mobility?  
Performance Engineering Magazine(TM) | Interested in high tech and computers? 
Marietta, Ga                         | Send ur snail-mail address to 
jgd@dixie.com                        | perform@dixie.com for a free sample mag
Need Usenet public Access in Atlanta?  Write Me for info on Dixie.com.
Newsgroups: sci.chem,sci.bio
From: t60bss9@mp.cs.niu.edu (Bijoy Sagar)
Subject: Methods for atrazine analysis
Organization: Northern Illinois University
Date: Thu, 24 Dec 1992 01:46:34 GMT



I am looking for reliable methods for the analysis of atrazine in waste
water. I am interested in methods that will not have interference with the presence of Nitrite, nitrate and Ammonia in the solution.

Thanks in advance,

Bijoy Sagar

Ps : I am an environmental Geochemist. How longer can ou get with those
      titles:-)
-- 
******************************************************************
| BIJOY SAGAR,               *|* ALL DISCLAIMERS APPLY.          |
| Dept. of Geology, Northern Illinois University, Dekalb, IL60115|
| Internet : t60bss9@mp.cs.niu.edu OR bijoy@geol.niu.edu         |
Newsgroups: sci.chem
From: billr@halcyon.com (Bill Ruediger)
Subject: SHORE A Hardness???
Organization: Northwest Nexus Inc. (206) 455-3505
Date: Sun, 3 Jan 1993 21:39:14 GMT

I want to make a project using a substance called Plastisol.
It is the material used in making those 'rubber' fishing worms that you
can purchase in sporting stores.

My project is similar to the worms, but not exactly.

Plastisol is made by the Ball Corp. (They make canning jars...)
I have contacted the Ball Corp. and they want some information from me
that I don't know how to give them.  They want Viscosity in Psc.. Which
I looked up and should not be too hard to determine.  They also want
something known as SHORE A hardness, which I know nothing about.  

Could someone please explain SHORE A hardness, or direct me to a good
reference.  Also if anyone knows more about Plastisol, and how it is
used, fused, and handled,  Please let me know.

billr@halcyon.com
- Bill Ruediger

Newsgroups: sci.chem
From: mikep@carina.unm.edu (Mike Prine CIRT)
Subject: Battery Chemistry info wanted
Date: Sun, 03 Jan 93 19:57:54 GMT
Organization: University of New Mexico, Albuquerque

	After looking through several books on batteries I failed to find some
of the information I wanted. Hopefully someone on the net can fill in the gaps.
	I am comparing Lead-Acid, Nickel-Iron and Nickel-Cadmium. While the 
books had adequate information for standard usage, typical voltages, 
charging-rates, cost and discharge characteristics, they were lacking in much 
specific information about what happens to batteries that are abused 
particularly on the discharge side. As Lead-Acid cells are in more common use 
I was able to obtain enough info about them but got conflicting statements on 
the Nickel types even in the same book.
	In particular I am want to know what chemical reactions take place
during cell polarity reversals and how detrimental they are to cell capacity
and life expectancy. Such reversals can occur in systems with poor voltage
regulation where one or more cells reach exhaustion before the rest of the
battery and are driven to a reverse polarity by the remaining cells forcing
current through the now discharged cell in an attempt to power the load.
	If you have any information on this I would appreciate it. 
Book references, if you have them, would be useful but please try to send the 
text as I might not be able to obtain a copy of the book quoted. If the 
information is restricted to a particular construction method like the 
pocket plate or sintered, Please indicate that in your reply.
A reply by email (instead or in addition to a post) would be appreciated. I
read sci.energy but not sci.chem on a regular basis. Thanks in advance
for any info you can supply.
-- 
Michael Lee Prine	 IRC (Information Resource Center) consultant
Internet: mikep@hydra.unm.edu, Bitnet: MIKEP@UNMB, Phone: 1-505-277-8135
I get most of my electricity, at home, from the sun. It's a hobby, 
who cares if it's cost effective yet.
Xref: sparky sci.chem:5559 sci.med:23089
From: mmm@cup.portal.com (Mark Robert Thorson)
Newsgroups: sci.chem,sci.med
Subject: Re: BEE VENOM:Who might need it in pharmacology
Date: Sat, 26 Dec 92 19:07:45 PST
Organization: The Portal System (TM)
Distribution: world

Is there an application for bee venom in conventional medicine?
Perhaps for de-sensitizing allergic individuals?

I recall that bee venom was once (almost 20 years ago) promoted as
a cure for rheumatism and arthritis, but I believe that has since
been shown to be quackery.  (I haven't got references;  I might be
wrong.)

If you want to get into bee-related homeopathic medicines, you might
consider royal jelly.  That is very popular in the Far East (e.g.
Japan, Hong Kong, etc.) and Germany.
From: ralf@ark.abg.sub.org (R.Stephan)
Newsgroups: sci.chem
Subject: Re: BEE VENOM:Who might need it in pharmacology
Date: 27 Dec 92 09:34:00 GMT
Organization: Not Very Ltd.

mmm@cup.portal.com (Mark Robert Thorson) writes:
> 
> If you want to get into bee-related homeopathic medicines, you might
> consider royal jelly.  That is very popular in the Far East (e.g.
> Japan, Hong Kong, etc.) and Germany.
                              ^^^^^^^
Um, not really.  And it's not a watered, I mean, homeopathic medicine.

ralf
--
***************
Sbetrg Pburerag
Newsgroups: sci.chem
From: mvp@netcom.com (Mike Van Pelt)
Subject: Re: Glow Cubes
Organization: Netcom - Online Communication Services (408 241-9760 guest)
Date: Wed, 23 Dec 1992 01:22:09 GMT

In article <1992Dec22.132040.2984@cnsvax.uwec.edu> douddy@cnsvax.uwec.edu writes:
>Has anyone ever heard of 'Glow Cubes?'  I remember reading somewhere
>that they were tritium isotope incased in a acrylic plastic block with
>trace Phosporous.

I haven't heard of these "Glow Cubes", but the "EXIT" signs in
commercial airliners are made this way -- I believe the plastic
in that case is polyethylene, and the tritium is not so much
"encapsulated" as the polyethylene's hydrogens are replace by
tritium.  I asked a friend in the airline industry if he could
snag me a couple, but he could not.

>The glow cubes were highly portable light sources with no
>external power requirements, putting out few watts of light for years.

But they're  (**-GASP-**) RaDiOaCtIvE!!!  Flee in terror, scream
and run in circles, assemble a mob of GreenPeecies with torches
and pitchforks... :-)

-- 
Mike Van Pelt          | What happens if a big asteroid hits Earth?
mvp@netcom.com         | Judging from realistic simulations involving a
                       | sledge hammer and a common laboratory frog, we
                       | can assume it will be pretty bad. -- Dave Barry
Newsgroups: sci.chem
From: indole@mace.cc.purdue.edu (Matthew Parker)
Subject: Looking for AI organic synthesis program
Organization: Purdue University
Date: Mon, 21 Dec 1992 08:29:05 GMT

I'm looking for a program to generate potential synthetic pathways given
a target organic molecule.  The program should include a database of 
commonly available starting materials (Aldrich + a few more, I guess.)
I'd like to run it on a 486 PC.  Does anyone know what's out there along
these lines?  I'd be interested in either commercial or public domain
software.

Please email my account directly.

Thanks,
Matt
indole@mace.cc.purdue.edu
Newsgroups: sci.chem
Subject: gene design
From: news@cine88.cineca.it
Date: 28 Dec 92 22:26:08 +0100

Pleas, I'm looking for programs for gene design.
Can you help me?
Answer to : lunazzi@boifcc.cineca.it (I have no feed to the news)
Thank you.
Mauro

Newsgroups: sci.chem
From: mulman@hmcvax.claremont.edu (Mike Ulman)
Subject: MOPAC 6.0 and a biradical product
Organization: Harvey Mudd College
Date: 30 Dec 92 12:39:59 PST



Hi!

Question:
In using MOPAC 6.0 to find the transition state between hex-3-ene-1,5-diyne and
the Bergman Cyclization product, 1,4-didehydrobenzene biradical, do I use the
keywords BIRADICAL and SINGLET in the subsequest saddlepoint, ts and force
calculations or do I simply use the starting and final optimized geometries
with no mention of BIRADICAL?

Thanks,

Mike

*******************************************************************************
*  Mike Ulman                                   909-398-4272                  *
*  Harvey Mudd College                                                        *
*  Department of Chemistry                 mulman@hmcvax.claremont.edu        *
*  Claremont, CA 91711                                                        *
*                                                    DoD#0634                 *
*  "Its gotta be loud, I want it to roar                                      *
*   I want it to blow everyone in the show right off o'the floor..."          *
*                                                       - Alice Cooper        *
*******************************************************************************
Newsgroups: sci.chem,rec.pyrotechnics
From: cheech@med.unc.edu (cheech@ocean.med.unc.edu (Greg Young))
Subject: Re: Glow Sticks
Keywords: Glow
Organization: UNC-CH School of Medicine
Date: Mon, 21 Dec 1992 21:15:20 GMT

In article <1992Dec18.192350.1630@muddcs.claremont.edu> sbonds@jarthur.claremont.edu (007) writes:

[Interesting discussion of glow sticks deleted.]

>
>So far as I know the only way to get the dyes needed is to synthesize them
>yourself.  If anyone knows otherwise, please let me know!
>
>  -- 007

A quick check of the Aldrich catalog shows:

26,419-9    9,10-Bis(phenylethynyl)anthracene        100mg     17.10

D20,500-1   9,10-Diphenylanthracene                   1g       17.70

The prices are a little steep, but a lot of the fluorescent materials
are effective at very low concentrations.  The diphenyl material looks
like the thing to play with but, given the perversity of the universe,
it probably has a tenth the fluoresence yield.

Greg


Newsgroups: sci.chem,sci.environment
From: ghg@en.ecn.purdue.edu (George Goble)
Subject: Re: Alternative refrigerants
Organization: Purdue University Engineering Computer Network
Date: Tue, 22 Dec 92 14:23:02 GMT

In article <1992Dec22.074145.1@bb1t.monsanto.com> bjgaed@bb1t.monsanto.com writes:
>In article <72070@cup.portal.com>, mmm@cup.portal.com (Mark Robert Thorson) writes:
>> With regard to refrigerants and alternatives to fluorocarbons, there
>> are many alternatives, though none combine the low flammability,
>> low toxicity, and chemical inertness of the various fluorocarbon products
>> (such as Freon).
>> 
>[Discussion of alternative refrigerants deleted]
>
>At the Organic Reactions Catalysis Society meeting last spring a paper 
>was presented by Leo Manzer of DuPont on their work on developing an 
>alternative to chlorofluorocarbon refrigerants.  Interest centers on 
>HFC-134a, CF3CFH2.  Contains no chlorine.  Targeted for the 1994-1996 
>time frame for phaseout of chlorofluorocarbons.
>
>-- 
>--Electric Monk            (Bruce Gaede); 
>                            e-mail: bjgaed@ccmail.monsanto.com
>
>"...and then time started seriously to pass."
>--Douglas Adams, _Dirk Gently's Holistic Detective Agency_


R-134a needs new equipment to run.  It is not miscible in R-12
mineral oils.  The PAG or Ester based oils used in R-134a equipment
are destroyed by the slightest traces of refrigerants with chlorine
(R-12 or R-22). R-134a has been found to cause testicle tumors in
Rats at 5% conc.  PAFT (program for Alternate Fluorocarbon Toxicity
tests) released last Sept.

Conferences have pointed out that attempts to "clean out" R-12 (CFC-12)
equipment in order to convert it to R-134a have generally not 
worked very well.  The few molecules of chlorides embedded in pipe
walls, etc, still come back and start the breakdown of the lubricants.
--ghg
Newsgroups: sci.chem,sci.bio
From: cfthb@ux1.cts.eiu.edu (Howard Black)
Subject: Re: Left-handed sugar
Date: Wed, 30 Dec 1992 16:36:42 GMT
Organization: Eastern Illinois University

In article <dexter.725655833@aries> dexter@aries.scs.uiuc.edu (The Gecko) writes:
>
>	I'm pretty sure that the enantiomer of D-glucose is L-idose, ie. that
>the named designation of a monosaccharide is absolute, rather than relative 
>to the D/L carbon.  This would make D- and L-glucose epimers at C-5, all the
>other stereocentres being fixed.

    "Epimer" is a pretty generic term, and usually refers to a single
stereocenter.  Thus, a phrase might be "epimeric at C-5".
    This has no bearing on the contention that D- and L-glucose are
epimeric only at C-5, which is just wrong.  D- and L-Glucose are
enantiomers, meaning that all four chiral centers are inverted.  If only
one stereocenter is changed, you make a diastereomer = different compound
with a different name.  Look it up.

>
>
>ie.			H-C=O			H-C=O
>			  |			  |
>			H-C-OH			H-C-OH
>			  |			  |
>		       HO-C-H		       HO-C-H
>			  |			  |
>			H-C-OH			H-C-OH
>			  |			  |
>			H-C-OH		       HO-C-H
>			  |			  |
>			H-CH-OH			H-CH-OH
>
>			D-glucose		L-glucose
					        ^^^^^^^^^
						  NOT!


-- 
   ******************************************************************
     Howard Black                             cfthb@ux1.cts.eiu.edu
     Department of Chemistry                  Eastern Illinois Univ.
From: BTCL_LTD@db1.cc.rochester.edu (Brian Connell)
Newsgroups: sci.chem
Subject: Chemistry in the Marketplace
Date: 29 Dec 92 01:22:31 GMT
Organization: University of Rochester, Rochester NY
X-News-Reader: VMS NEWS 1.11

Several months ago I remember a discussion about various chemicals used in the
household. One of the books mentioned (I believe) was Chemistry in the
Marketplace. Could someone please tell me the author and possibly the publisher
of this book? Are there any other (good) books currently in print that discuss
common household chemistry?
 
Thanks alot!!! (and sorry if you see this posting twice)


 


--
Brian Connell                                     University Of Rochester
Internet: btcl_ltd@dbv.cc.rochester.edu           CPU Box 271361
Bitnet: btcl_ltd@uordbv                           Rochester, NY 14627
Xref: sparky sci.chem:5540 sci.environment:13803
From: ahgrabow@apgea.army.mil (Alexander H. Grabowski <ahgrabow>)
Newsgroups: sci.chem,sci.environment
Subject: Re: Alternative refrigerants
Date: 22 Dec 92 20:02:24 GMT
Organization: CBDA, Edgewood, Md

In article <1992Dec22.074145.1@bb1t.monsanto.com> bjgaed@bb1t.monsanto.com writes:
>At the Organic Reactions Catalysis Society meeting last spring a paper 
>was presented by Leo Manzer of DuPont on their work on developing an 
>alternative to chlorofluorocarbon refrigerants.  Interest centers on 
>HFC-134a, CF3CFH2.  Contains no chlorine.  Targeted for the 1994-1996 
>time frame for phaseout of chlorofluorocarbons.
>
I have contacted DuPont and Bayer on that topic, since we are
*strongly* interested in drop-in replacements for CFCs

From what I heard I understand that the acute toxicity as well as the 
subacute long-term toxicity is too high to allow HFC-134a to be used 
in industrial processes.

If anybody has different information on that, I really would be happy
to hear more about it.

Alexander
__________________________________________________________________
| Don't call us, we will call you    |  Ain't got no brains.     |
| Don't flame me, I won't flame you  |  Ain't got no opinion.    |
|                                    |  Ain't got nuttin' to be  |
| ahgrabow@cbda8.apgea.army.mil      |  held responsible for.    |
| "Only the narrow-minded worry about typos"                     |
|                                  (J.Michener)                  |
|________________________________________________________________|
Newsgroups: sci.chem