Where it is difficult to substitute natural resources, the skills of planning and managing natural resources will take priority over other strategies.
This paper will focus on a set of critical materials, mostly named as single elements, that are metals, at risk of supply constraints, have environmental implications, financially costly, price volatile, deemed economically important and are difficult to substitute as a result of their unique properties or for economic reasons.
Interestingly, SD13M is included in the region of chromosome 13 that was difficult to substitute from strain B6 to MSM during the course of establishing a consomic strain [ 21].
And it may be difficult to find a way to substitute these losses.
"It is going to be difficult to argue that Atlantic City is a direct substitute".
In fact, arrowroot starch, available in most health food stores, makes a good substitute for water chestnut flour, which can be difficult to find.
They can be difficult to find, but light corn syrup, also an invert sugar, makes a good substitute.
Both Britain and Sweden "have had to face a situation the electricity they generate from existing reactors would be extremely difficult to substitute with anything else but nuclear," Luis Echávarri, director general of the Organization for Economic Cooperation and Development's Nuclear Energy Agency, an organizationthat advises industrialized countries, said.
Mr Gleave says it would be incredibly difficult to substitute the aircraft parts or to cover up the damage.
It has been difficult to find substitutes that match the function and performance level of PFASs.
