The phrase "and difficult to realize" is correct and usable in written English.
It can be used when discussing concepts, ideas, or goals that are challenging to achieve or implement.
Example: "The project aims to address complex issues that are often overlooked and difficult to realize in practice."
Alternatives: "and hard to achieve" or "and challenging to implement".
On the other hand, the encapsulation of ethane/ethene onto the inner surface of considered nanotubes is endothermic and difficult to realize with an appreciable energy barrier.
However, this appeared to be expensive and difficult to realize.
The channel of diffuser/nozzle tube proposed by Stemme was complex and difficult to realize micromation, and some regions even played a role of preventing the pump from working effectively.
Although the latter may be considered a more accurate method, it is more complex and difficult to realize during the daily practice.
There is considerable concern among NGOs and other stakeholders in India that the DBT's goals are too broad and difficult to realize.
Currently the inductor is only used where necessary, for a number of reasons: (1) compared to the capacitor and resistor, inductor is expensive to manufacture, and particularly difficult to realize in microcircuit form.
However very thin diaphragms results in more non-linearity and are difficult to realize.
However, it has not been considered favorably from a systems point of view since it breaks the Internet layering structure and is difficult to realize among ISPs with standard hardware routers.
These algorithms involve more computational complexity and less regularity and are therefore difficult to realize in hardware [5].
However, for complex, large systems, global control and optimization are difficult to realize using a limited number of targets and control variables; a target system that is more comprehensive and can efficiently control the key processes and characteristics becomes indispensable.
However, direct observation of cows on pasture is time consuming and can be difficult to realize.
