Natural Science Forum / Chemistry / Analytical Chemistry / February 2006

You should give EZChemDB a try.  I downloaded a trial from
www.makeitez.com and the program was surprisingly good!  Unlike most
engineering programs, an individual can afford it as well. The database
is easy to use, and it has temperature dependent properties for over

While making dilutions of 1000 ppm potassium standard, I noticed soapy
bubbles in the solutions indicating some kind of added surfactant in
the standard. The bottle didn't mention any additive. I never noticed
such thing in AAS standards of transition metals which are highly

I have an question regarding the position of chopper used to eliminate
the effect of flame and atomic emission. Let me try to draw a block
diagram of typical AAS:
Lamp -----> Chopper ------> Flame(containing atomic vapor) ---->

This is a question from an old textbook on optical methods of analysis:
Q. Why is true double operation (alternately observing sample and
reference ) feasible for a fluorometer but a not a spectrofluorometer?
I don't understand his question as to what the author is trying to ask.

I was looking the official methods of AOAC for determination of
sodium/potassium in fruits by flame photometer. What surprised me is
the statement : Note the %T of standards. Does transmission (or
transmittance ) have a certain meaning in emission spectroscopy? I

i want to kno about the jobs related with analytical achemistry.
pleas stay in touch.

i once heared that if u use a phosphatebuffer on an hplc system for a
long time, it is possible that bacteria and other microorganism can grow
in this habit. I also heared that it should be possible to clean this
mess with HNO3 solution.

I would appreciate your kind help in answering this basic question ( I am a
beginner):
does exist a significative diffence (if any) in quantitative data obtained
with a GC-MS in comparison with a GC-FID ones?

Fumair Ltd are UK manufacturers of high quality laboratory fume cupboards,
fume extraction systems and airflow monitors.
Our fume cupboards are manufactured as standard using unique low
maintenance, long lasting panels of chemically resistant, fire retardant

Does anyone know of a program that will convert the Varian Star *.run
files to a text file or something else I can use in excel. I have a lot
of files from a Varian HPLC machine which uses the ancient 4.51 star
software, which I can't for the life of me work out how to

have this happend to you?i have an unknown material and i think it is
poli ole.i have asked a analytic center to find it for me exatly by
using gc-ms .they said it is impossible and we should know what is the
material for using gc-ms.

Editor's Page
....nothing is WORSE than Shimadzu's infamous reputation in the
analytical instrumentation field!
January 2006

Hello everyone;
I am trying to develop and LC-MS assay where I apply my sample
(carbamazepine) to a reversed phase column with an aqueous buffer (1)
(can't use organic in this one) and then I wash the column with a MS