Hello netters, I would like to know if anybody in this newsgroup has
any pointers to any type of a simple process that would yield gaseous
chlorine from preferably solid precursors. In particular I am looking
at a process that would be very temperature sensitive, so that I could
control the amount of chlorine emitted just by using a servo loop on the
pressure of the gas. The amounts of gas needed are tiny, since 1g of the
gas would probably last a long time.

The gas will be injected into a vacuum chamber where it will be used to
etch various materials.

Of course I could just buy a bottle of Cl2 and a regulator, but then the
presence of so much Chlorine around our system would raise plenty of safety
issues.

Thank you for any information in this matter.

Stefano Concina

This is a trivial little question but the phenom puzzles me. If you heat up
a pan of water, you usually don’t see a vapor cloud until immediately after
you turn off the heat (we’re using a gas stove, so the heat removal is
immediate), even if you haven’t brought the water to a boil. Clearly water
molecules are escaping from the liquid both before and after the heat is
removed. Yet only after the heat is removed does one see fog formation. Now
its easy to say that the heat prevents the cloud from forming. My problem
with this is that the heat source is beneath the pan, and it doesn’t seem
possible that the air temp above the pan could be so suddenly cooled that a
fog could form. After all, the formation of the fog is almost immediate
after the heat is removed.

Any ideas?

Some time ago someone asked about the possibility to calculate protein
structures. I forwarded that message to some other newsgroups, commenting
that I was not sure that the xray or nmr determined structure is the same
as the natural (in vivo) structure. Here is what I got:

NOTE: Don’t ask me about details, please use the quoted e-mail adresses!
===========================================================================

From: r…@nmrvex.biochem.mpg.de (Alfred Ross)

Hi Rolf

another possibility beside XRAY is the use of nuclear magnetic resonance spectroscopy. Within this field an effect the so called "NUCLEAR OVERHAUSER EFFECT" is
know which contains information about distances between protons.
If you have this information about many pairs of protons you can based on geometrical calculations determine the structure of a protein.
If you want to know more – mail me.

Alfred

From: stebbic%darst-sgi.ROCKEFELLER….@ROCKVAX.ROCKEFELLER.EDU (Charles Erec Stebbins)

        There is at present NO method to calculate 3-D structure of a protein (if by t.s.
tertiary strurcture).  I wouldn’t be slaving away in x-ray xtallography if it were
any different, believe me.  As for whether the xtal structure is the same as the cell
structure, of course there is no way to know, but for several reasons I think it is
fairly well accepted that they are the same:

        1)  Biological proteins usually denature rather than take on alternate
            conformations (unless it has n-fold FUNCTIONAL conformations, in which
            case it will still tend to denature rather than assume these cell
            event specific conformations in non-biological conditions)

        2)  The xtal structures usually match other data and clarify the
            mechanism by which the protein functions.  

        3)  Conditions in a xtal are actually not that different than a
            cell (at least as far as hydration is concerned).

Erec Stebbins
The Rockefeller University

===========================================================================

–

—————————- <- cut here -> —————————-
rolf elak  r…@nite.toppoint.de | Disclaimer:  Neither my employers
D-24114 kiel                    | opinions nor my own. Just a road-
N-8270 drag                     | kill on the informational highway…

Hello everybody,

I just got the MOPAC 6.0 sources for unix-systems from
ftp.funet.fi.
When I tried to compile, an error occured during compilation
of the file deriv2.f.
The error message was concerning some array indexes.

Has someone successfully compiled MOPAC 6.0 on an
IBM RS/6000 machine and can give me some help ??

Thanks in advance,

Helmut Schmidt

+—————————-+——————————————-+
| Helmut Schmidt             | Pfaffenwaldring 57                        |
| PVDF-Labor                 | 70550 Stuttgart, GERMANY                  |
| 1. Physikalisches Institut | email: schm…@pi1.physik.uni-stuttgart.de|
| Universitaet Stuttgart     | Phone: +49-711-4907 Fax: -4886            |
+—————————-+——————————————-+

Dear all,

I want to ask a question:

Should the Calibration graph for the Flame Photometry (direct-Intensity method)
be plotted as a straight line or a curve?

Thanks for you all the kind help!!

Hi,
        I wonder if anyone out there could offer any useful
suggestions.
A major part of my project is to construct a partition
device based on Flow Injection Analysis. Basically,
under HPLC conditions (to mimic petroleum reservoir conditions)
I want to determine the partition coefficients of selected
compounds in solvent/water and oil/water systems.
At present, I understand how to introduce the solvent and
water into a mixing column where the spiked compounds will
partition between the two phases under temperature and
pressure conditions typical of petroleum reservoirs.
However, I envisage there will be problems separating the
solvent and water upon leaving the mixing column again
under temperature (c. 90C) and pressure.
        Gravity separation has been applied so far.

                                .——
                                | sssss —->                s = solvent
                                | s.—
                                | s|
                                | s|
                                | s|
                        ——–’ s|
(Mixing column)  —->  swswswswsw |
                        ——–. w|
                                | w|
                                | w|
                                | w|
                                | w’—
                                | wwwww —->                w = water
                                ‘——
As in the diagram to determine partition coefficients
it would be simple to determine the concentrations
of compounds by analysis of the separated oil and water.
However, its not so simple as the picture depicts.
        Does anyone know any other physical methods to
obtain the said fractions? Or does anyone have experience
with such equipment? The Flow injection analysis method is
commonly used in the water and pharmaceutical disciplines.
I look forward to any useful comments or ideas.

cheers
        Doc Bazzer.

I am looking for someone who can provide info on GC olfactory CHARM
analysis of flavour or volitiles.  References or other types of info
would be greatly appreciated.  I am familiar with sniff port analysis and
have access to statistical software.  Thanks in advance to anyone who can
help!

–
****************************************************************************
*  Ron Skinner                       ***     Food Chemistry Lab Manager      *
* E-Mail rskin…@peinet.pe.ca      | | *    Prince Edward Island            *
* Ph 902-566-1725                  /—\ *   Food Technology Centre          *
* fax 902-566-5627                (_____) *  Charlottetown PE Canada C1A 7N8 *
*****************************************************************************

If 750 mg of GABA (Gamma-Aminobutyric acid were ingested 3 times a day,
along with B6, would it cross the blood-brain barrier?  I’ve heard that
it helps with anxiety.

Frank
—

I was searching for a general equation that would summarize the basics of
a flame (bunsen burner). I am looking for any equations on flame heights,
sizes, parts, etc. for a project. I already have an equation on heat
conservation but I need more equations on flame characteristics to model
a flame.
—
 ANIRVAN CHATTERJEE (and BoB the almanac) // finger anir…@crl.com for my FAQ!
     anir…@crl.com // chat…@mvhs.srvusd.k12.ca.us // anirv…@aol.com    
    GCS/E/S/SS/O d? p– p++ c+++ l? u e(+) m* s-/? n+ h f+ g+ w+ t+++ r !y