The phrase "ascertain composition" is correct and usable in written English.
It can be used in contexts where you need to determine or identify the components or elements of something, such as in scientific or analytical discussions.
Example: "In order to understand the material's properties, we must first ascertain composition through rigorous testing."
Alternatives: "determine the makeup" or "identify the constituents".
Prepared samples were characterized by different techniques to ascertain their composition, surface chemistry, morphology, and surface physics, determining their electrochemical capacitances in acidic medium.
To ascertain the composition and the factors affecting the viscosity of RA, some samples were prepared in the case of different conditions of mixing temperature and processing time for different rubber dosage and rubber size.
The two samples were initially sent to external laboratories to ascertain the composition of each and to confirm what percentage of aluminium would be found.
Nagumo quickly reversed his order to re-arm the bombers with general purpose bombs and demanded that the scout plane ascertain the composition of the American force.
We were able to ascertain household composition for 68.1% of selected households and enrolled 401 (65.3%) eligible adults into the study.
In order to ascertain body composition, quantitative nuclear magnetic resonance (qNMR) imaging was carried out at 14 weeks of age (Fig. 2E).
The choice of a classification cutoff score is always subjective, but an analytical approach permits to ascertain the composition of the recovery sets during the search of a database, and also enables controlling the inherent tradeoff between precision and recall [ 59].
In that enumeration people were asked to specify their ethnic identity, generally the best way to ascertain the ethnic composition of a population.
To ascertain the chemical composition and porosity of the HsGDY coatings, some discrete HsGDY nanotubes are intentionally fabricated by removing the NiCoHC by acid etching process, which would otherwise affect the 13C nuclear magnetic resonance (NMR) analysis due to the presence of paramagnetic species (Co2+) and interfere with the N2 adsorption/desorption (Supplementary Fig. 6).
