From the PhD thesis to a journal I'm on the task of transforming sections of my PhD thesis (field: Economics) as journal articles. I would like to know which are the key differences between these two formats, so I can optimise the task. I can think of three essential aspects to have in mind:


explain less. A thesis is supposed to be for a much wider audience, whereas journal articles are normally read only by those in that particular subfield. 
assume more. Kind of the same thing, but important, for example, when citing papers. You can assume people is aware of them.
repeat less. Theses are long(ish), whereas articles are short(ish). In theses one reminds the reader of things in previous sections. For example, repeat an important equation listed twenty equations ago.


To me these are vital, but I could be wrong, and maybe you have more experience on this. Even if from other fields, I would very much appreciate your wisdom on this.

PS: I found this partly related question but to me answers seem highly unsatisfactory, as they focus more on processes than in actual content.
In some fields it is possible to publish long papers, in which case something very like your dissertation might be acceptable. 

However, you seem to suggest you want to divide out parts of it for separate publication. This can be a good idea, of course. 

The best advice I can give is that each paper should be complete without being pedantic. You still need to cite everything, but those things that are generally known to professionals/academics needn't be explained in a paper as they might have been in a thesis. 

Can a working professional be expected to understand your paper without spending too much time chasing references? If the answer is yes, you are probably pretty close to the mark.