chemical analysis, SPLITS AND BANDS chem.

[Utah]

Уважаемые коллеги, подскажите, пожалуйста, кто силен в лабораторных химических анализах, что такое SPLIT и BANDS в отрывке, приведенном ниже. всем спасибо огромное.

For the samples you plan on collecting, we recommend you analyze for the following parameters:
- Total Petroleum Hydrocarbons (TPH) - aliphatic/aromatic SPLIT would be ideal, if the lab can do it. Also, if the lab can look at the different carbon BANDS, or provide a gas chromatograph (GC) output, that would be very useful to determine the nature of the hydrocarbons present.