Rules for Ordering Elemental Analysis Service

You can essentially improve the quality of results gained for you in the Microynalytical Laboratory:

• Please transport your samples in well closed and clearly labelled vials. When selecting your sample identification please mind, that the label should be readable, understandable and reproducible within our reports (e.g. avoid to use greek letters, super- and subscripts). We advise you to use two or three letters to identify the orderer/producer of the sample followed by a number. Avoid to use one declaration repeatedly but rather add an incrementing letter or number to indicate repeat of investigation or preparation. Enclose a description sheet or send closer information with fax or e-mail. For a correct manipulation of substances we need information on stability and known properties. Please declare the sum formula according to your assumptions. This enables us to avoid errors introduced by known interferences with hetero elements. If you want to use elemental analysis to prove absence of an element (e.g. halogenes) also make a remark on the limiting values. Then we can state the significance of our results according to your request.
• It is not always sufficient to confirm the necessary amount of substance (2 to 5 mg per analysis) is shipped according to your weighing. We have to be able to collect the material and transfer it to the tin capsules or platinum boat for mineralization. Especially oily substances can hardly be transferred quantiatively. Use sample vials as small as possible to hold your material. We offer to keep remaining material and return it to the customer. Therefore we advise you to send excess substance which enables us to confirm results by repeating a determination.
• We advise you to order at least a double determination if no stoichiometric composition can be assumed. If we receive technical or environmental samples we refuse single runs. We rather believe three or four replicates are necessary if the material looks inhomogenous.
• Concerning samples including hetero elements we want to point out, that C/H/N analysis does not always lead to a clear conclusion. Determination of oxygen, halogen, sulfur or phosphorus can frequently indicate a possible interpretation if C/H/N values cannot confirm the assumed formula. Very often one can conclude assumptions on the course of a reaction towards unexpected or unwanted main- or byproducts. C/H/N/S determination is possible within a run at the same substance amount necessary for one C/H/N analysis. So you should prefer ordering C/H/N/S for the characterization of sulfur containing substances.
• We must rely on your comments on instability of samples. If you need different determinations made on a single instable sample please enclose aliquots in different sealed vials to minimize contact of the samples to light, moisture, and air. We are not equipped to manipulate material in an inert atmosphere and can only guarantee to minimize the contact time of sample to moisture and air to some minutes, the time necessary to weigh in the sample.

  Vienna, September 1996