I'm writing up my dissertation and I'm really confused where to use "the". Examples:
In this experiment, (the?) heat transfer coefficient was calculated, allowing to estimate (the?)frost thickness.
And:
Firstly, (the?) air properties are defined.
And:
As (the?) crystals grow in radius, the amount of air in (the?) ice is reduced, due to (the?) ice becoming more packed.
None of the nouns mentioned above have been used for the first time, so I rule out the use of "a".
Would appreciate any help.
Best Answer
The is appropriate in each of the places you have a question about:
Here, allowing is incorrectly used, since it needs an object (*allowing someone to estimate...*). It would be better to use something else:
...
...
As you said, a would not work because in each case, you're talking about a specific pre-introduced or pre-defined entity. There are times when you would want no article, but in these examples, you would want the. See the Wikipedia article: