"observed separately" is correct and usable in written English.
You can use this phrase when you want to talk about observing something on its own, distinct from other objects or people. For example: "The two species of ants were observed separately to study their behavior."
At these locations, bioclimatic potential was observed separately for each of the last five decades.
Violations of charge conjugation and parity have been observed separately, but when the reversible arrow of time is considered, the symmetry of the three together seems to hold.
These trends were observed separately in each monkey (Supplementary Fig. 4a, c) and also when the analysis was performed on a neuron-by-neuron basis (Supplementary Note 2, Supplementary Fig. 4d f).
Ni-based catalysts have been used for this reaction; however, the Ni size effect and support effect were highly coupled and therefore could not be observed separately.
Deuteration of one of the phospholipid layer is performed to allow each monomolecular layer of the bilayer to be spectroscopically observed separately.
To monitor the stability of coating even at high temperature, the thermal expansion coefficient of glass and steel was observed separately.
In addition, we have observed separately-caged cicadas of Kobonga umbrimargo, K. apicans, and Pauropsalta "near extrema" responding positively to C. leucoviridis clicks.
In practice, both types of imbalances are frequently observed both separately and in combination.
Mothers were then observed interacting separately with each twin, and provided DNA samples.
Interestingly, the simultaneous addition of CHR and CAT at equal concentrations provoked a higher Ca2+ increase (Figure 1C) than the sum of effects observed by separately added peptides (Figure 1B and C), suggesting that CHR and CAT may have synergic effects on the transient Ca2+ entry in PMNs.
To accomplish this challenging task, several strategies are commonly observed either separately or in combination.
