"not fully understood yet" is grammatically correct and commonly used in written English.
It can be used to describe something that is not completely comprehensible or clear at the current moment. Example: The new software update had some glitches that we have not fully understood yet.
However, due to its complexity, this process is not fully understood yet.
The process of absorption and diffusion of atomic hydrogen through a metal is not fully understood yet.
However, the agglomeration effect is not fully understood yet due to the worse description of the morphological evolution of agglomerates during reaction.
TiCl3, ScCl3 or CeCl3 are known to be efficient dopants but the details of the catalytic mechanism are not fully understood yet.
The resistance of a diffusion boundary layer and consequently mass transfer of the IA through the anion exchange membrane under these conditions are not fully understood yet.
The mechanisms by which activity and stability are enhanced after the heat treatment of these Fe– and Co N/C catalysts are not fully understood yet.
The use of two homogenization units (e.g. orifices) in series thereby is generally accepted as increasing homogenization efficiency, even when the mechanism is still not fully understood yet.
Their biological effects are not fully understood yet, but it is well known that US have effects on organic tissues when their mechanical energy is converted into thermic energy.
Palynological studies carried out in the Balearic Islands highlight a deep vegetation change from the mid- to late-Holocene, but the climate-environmental-human interactions are not fully understood yet.
Noninvasive NIRS is shown to be a suitable method to get more direct information about neuronal-activity-associated changes in cerebral parameters which are partly reflected in BOLD signal but are not fully understood yet.
Although a strong impact of humidity on polymers and the formation of their molecular network is known, the complex interactions between humidity, temperature, diffusion, reaction kinetics, rheological behaviour and mechanical properties are not fully understood yet.
