Newsgroup sci.chem.analytical 9018

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Does anyone know where on the net i could get more information about 
atomic force spectroscopy?
Alexei

Information regarding FBI Laboratory Division examiner positions can be
found at
http://www.fbi.gov/over/labpers.htm

Dear Analytical Chemists,
I am setting up a new lab and I have inherited from the former
occupant a Waters Prep LC 2000 system with a 486 Tunable Absorbance
Detector and Waters 4000 System Controller.  I'm not sure of the 
vintage of this machine and there is no documentation to be found
to help in resuscitating this instrument.  If anyone has one of 
these HPLC systems I would appreciate some information regarding the 
setup.  Please contact me directly at the email address below.
		Best regards,
				Tom O'Connell
**********************************************************************
| Thomas M. O'Connell 			                             |
| Assist. Prof., Medicinal Chemistry                     	     | 
| School of Pharmacy, CB #7360		phone (919) 966-2956         |
| University of North Carolina	        fax   (919) 966-6919         |	
| Chapel Hill, NC  27599-7360           email tmoc@gibbs.oit.unc.edu |
**********************************************************************

Dear friends:
HELP!  I am a grad student at Rutgers University, New Brunswick NJ.  I am
searching for an instrument with which to measure millimolar (or better
yet, micromolar) concentrations of H2 in the headspace of culture vessels.
From what I understand, there are two instruments which fit the bill.
One is a GC equipped with a molecular sieve column, an oven which can be
programmed to run a temperature gradients (or a dual detector,) and a
TCD.  One would use Ar or N2 as the carrier gas.
Even more sensitive is a trace gas analyzer, equipped with a reducing
mercury hydrogen probe.
If anybody knows of such an instrument in the NYC - Philadelphia area
which could be used periodically, I would be very grateful of any
news.  So far, I have not been able to locate one at RU, at least one
which is currently operational.  I would value any leads whatsoever.
Thanks for any assistance on this matter.
Nick Landau
Dept. of Biochemistry and Microbiology
Rutgers University Cook College
New Brunswick NJ

We have an old microtome with a label "MSE", but we do not know whether
that is the name of the manufacturer. We want to buy a new one but do
not know the supplier.
We are looking for a microtome with the following characteristics:
1. the sample that has to be cut into slices of some micrometers are
expandable polystyrene beads of a diameter between 3 and 5 mm.
2. The sample is fixed by a holder with a hole of 1.5 mm to which vacuum
is applied.
3. A horizontal razor blade that makes a left-right movement.
4. The sample holder has a mechanism to move toward the razor blade and
to adjust height.
If you want I can send you a schematic drawing.
Thanks in advance for your help.
Wouter Hagens

WTB DEC PDP 11/73 , Q-BUS, LSI-11, LAB EQUIPMENT BUILT WITH DEC
EQUIPMENT / ETC.  ALSO SIGMA BOARDS, WYSE TERMINALS.
MARTY PAULINS
MAP & ASSOC., INC.
614-592-6890

I am looking to purchase a complete HPLC system with an autoinjector/Diode
array detector/gradient pump/computer control.  I would consider a system
that does not have all the options provided I can still purchase the
additional pieces from the manufacturer.
I am also looking for an FTIR, DSC, TGA, microscope, IR microscope,
UV-Vis, and a light scattering detector suitable for interfacing to an
HPLC.
Thanks
Mark Vreeke
510-748-6932

Nicholas Landau wrote:
> 
> Dear friends:
> 
> HELP!  I am a grad student at Rutgers University, New Brunswick NJ.  I am
> searching for an instrument with which to measure millimolar (or better
> yet, micromolar) concentrations of H2 in the headspace of culture vessels.
> 
> From what I understand, there are two instruments which fit the bill.
> 
> One is a GC equipped with a molecular sieve column, an oven which can be
> programmed to run a temperature gradients (or a dual detector,) and a
> TCD.  One would use Ar or N2 as the carrier gas.
> 
> Even more sensitive is a trace gas analyzer, equipped with a reducing
> mercury hydrogen probe.
> 
> If anybody knows of such an instrument in the NYC - Philadelphia area
> which could be used periodically, I would be very grateful of any
> news.  So far, I have not been able to locate one at RU, at least one
> which is currently operational.  I would value any leads whatsoever.
If ALL you want to see is hydrogen... all you need is a helium leak detector 
retuned for mass 2 instead of mass 4.  Nanomolar should be a snap, with 
infinitesimal sample size.  Calibrate with a permeation tube.
-- 
Alan "Uncle Al" Schwartz
UncleAl0@ix.netcom.com ("zero" before @)
uncleal@uvic.ca        (to 30 July, cAsE-sensitive!)
http://www.ultra.net.au/~wisby/uncleal.htm
 (Toxic URL! Unsafe for children, Democrats, and most mammals)
"Quis custodiet ipsos custodes?"  The Net!

On Sat, 12 Jul 1997 17:44:16 -0600, analyzer@aol.com wrote:
>Greetings chemistry fans!
>
>I need to monitor a process gas scrubber outlet for H2S.
>During normal operation, no H2S is present. When an
>upset occurs, all the H2S is not scrubbed out and it
>passes with the outlet gas. We don't need an "analytical"
>montoring method, but only need to know when H2S is present.
>Minimum detection in the 1-5 ppm range is fine.
>
>
>I am aware of the following existing methods:
>
>1. Electrochemical sensor -- this is out because SO2
>   is present at levels high enough to poison the sensor.
>
>2. Lead acetate paper tape -- this is $15-20,000. Yeow!!
>
>3. A Tin-based solid state sensor -- realitively new,
>   and untested in this application.
>
>Anyone have experience with a similar situation? If you
>can help me out, your reward will be a laurel, and hearty
>handshake... Thanks in advance!!
>
>The typical sample stream composition is:
>
>N2	       28.60 %
>H2O	        0.00
>O2	        2.47 %
>SO2	      450.00 ppm
>H2S	        0.00 ppm
>Methane	        3.71 %
>Ethane	        4.38 %
>Propane	       37.25 %
>Propylene	0.39 %
>n-Butane       15.80 %
>I-Butane	4.99 %
>Butylene	0.14 %
>c-2-Butene	0.04 %
>t-2-Butene	0.03 %
>i-Pentane	1.36 %
>n-Pentane	0.61 %
>C6+	        0.29 %
>
>Thanks if you read this far! Give yourself the Mr. Wizard
>secret handshake!
>
>-------------------==== Posted via Deja News ====-----------------------
>      http://www.dejanews.com/     Search, Read, Post to Usenet
Flame Photometric detection of H2S is a very accurate method of
quantitative analysis especially for low concentrations and would not
have the problem of cross interference associated with some other
techniques in this application.  The Columbia Scientific SA285
provides high speed and high sensitivity analysis and is well suited
for concentrations between 50 ppb and 1 ppm.
Columbia Scientific is now a division of Forney Corporation and can be
contacted at 800-356-7740 and has a web site at www.forneycorp.com
Hope this helps.

In article <33cf4883.12340329@nntp.ix.netcom.com> richtx@ix.netcom.com (Rich Missler) writes:
>>I am aware of the following existing methods:
>>
>>1. Electrochemical sensor -- this is out because SO2
>>   is present at levels high enough to poison the sensor.
>>
>>3. A Tin-based solid state sensor -- realitively new,
>>   and untested in this application.
Alas, both of these technologies require the presence of oxygen, or the sensor 
signals will rapidly fade. Oxygen is needed for the counter-electrode reaction 
in the EC sensor and to replenish the O2- ions in the stannic oxide based 
sensors.
I, too, think flame photo is your most likely and off the shelf solution.
Bill
************************************************************
Bill Penrose, President, Custom Sensor Solutions, Inc.
   526 West Franklin Avenue, Naperville IL 60540, USA
   630-548-3548, fax 630-369-9618, email wpenrose@interaccess.com
************************************************************
Purveyors of contract R&D; and gas sensor-based product 
development to this and nearby galaxies.
************************************************************

William R. Penrose wrote:
> 
> In article <33cf4883.12340329@nntp.ix.netcom.com> richtx@ix.netcom.com (Rich Missler) writes:
> >>I am aware of the following existing methods:
> >>
> >>1. Electrochemical sensor -- this is out because SO2
> >>   is present at levels high enough to poison the sensor.
> >>
> >>3. A Tin-based solid state sensor -- realitively new,
> >>   and untested in this application.
> 
> Alas, both of these technologies require the presence of oxygen, or the sensor
> signals will rapidly fade. Oxygen is needed for the counter-electrode reaction
> in the EC sensor and to replenish the O2- ions in the stannic oxide based
> sensors.
> 
> I, too, think flame photo is your most likely and off the shelf solution.
> 
> Bill
Have you thought about molecular absorption?  BOVAR Western Research
produces great products for H2S, SO2, NOx analysis both for CEM systems
and sulfur plant control.
For more info try calling 1-800-661-9198
Greg

Reply to: morgul@worldnet.att.net (h)
Responding to: algov@aol.com (Algov)
>Does anyone know where on the net i could get more information about 
>atomic force spectroscopy?
     Use a search engine.
                                     h
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Dear netters:
    I am looking for isocratic or simple gradient HPLC systems for the
student lab. One of the best deals is offered by GBC Separations. If
anyone has experience with them, I would greatly appreciate answering a
few questions:
- how reliable are the systems?
- how their spindle-driven pumps compare with the traditional cam
design?
- what is the quality of their customer service?
- The systems are produced in Australia. How does that effect the
delivery time, availability of parts, etc.
Thanks in advance, regards
Alexey Eliseev

We are looking for a company to build 3 continuous on-line analyzer
systems.We will specify the analyzers, but need a panel shop with
engineering expertise to design the sampling systems, etc., and put them
together. (Doesn't need to be a local company for us.)
Would appreciate any feedback from suppliers or (better yet) those with
experience dealing with an analyzer system integration company. (Thumbs up
or thumbs down appreciated also!!)
Start-up, training and field service capabilities are a plus.
(Would consider an individual working on contract with us for this also)
Thanks folks!
Harry LaRone
Los Angeles

HO>Reverend Chuck wrote:
HO>> 
HO>> 
HO>> Best idea since using hydrogen to lift commercial passenger zeppelins.
HO>> 
HO>If you read your history, the Hindenburg disater occurred because
HO>America refused to sell safe helium from it's monopoly supply to a
HO>regime of which they did not entirely approve. 
HO>As people do, faced with an obstacle the German engineers used an
HO>alternative that was less safe.
Yes, and they scrapped the zeppellins AFTER they had aquired a helium
source. And you know what hitler said about them. He didn't like cats
either.
HO>The USA cannot ascribe all blame to the engineers, or vice versa.
HO>If you look around the world today, some countries are using what we
HO>might judge as insanely dangerous nuclear technologies because they are
HO>denied access to the sophisticated and safer technologies that have
HO>already been explored by other countries and are withheld from the world
HO>community for largely political reasons.
HO>Nuclear technology is NOT complicated, unless you also want to make it
HO>very safe. If other countries are desperate enough for the electrical or
HO>political power, they will build reactors out of chewing gum and string,
HO>and they will mostly work. The incredible thing about Chernobyl is that
HO>it didn't happen a dozen times before. It will also happen again, in
HO>some guise.
HO>Nick Hoffman	Geophysicist Extrordinaire
HO>		"Insert Disclaimer of your choice here"

We are looking to purchase or lease equipment for the analysis of air
samples by EPA Method TO-14.
We need everything except the GC and detector.
ie Sample introduction/concentrating equipment, cannisters (SUMMA, 
6 liter) canister cleaner,
autosampler, etc.
Good second-hand equipment is preferred.
Any recommedations for suppliers would be appreciated.
Thank you,
Ryan Watson
Walsh Environmental

(303) 443-3282
(303) 443-0367 fax