addition of a few new concepts

[schumannj]

I was missing a few concepts for annotating some quantities and sections in NOMAD:

• sample | en | The material of interest in an investigation.
• mass | en | The weight of an object.
• reaction conditions | en | Collection of environmental variables of a reaction such as temperature, pressure, reagent concentrations and flow rate.
• mechanism | en | A detailed description of the process leading from the reactants to the products of a reaction, including a characterization as complete as possible of the composition, structure, energy and other properties of reaction intermediates, products and transition states.
• elementary reaction | en | A reaction for which no reaction intermediates have been detected or need to be postulated in order to describe the chemical reaction on a molecular scale. An elementary reaction is assumed to occur in a single step and to pass through a single transition state.
• person | en | A physical entity which is a human beeing.
• preparator | en | The person carrying out a synthesis preparation.
• experimenter | en | The person starting or carrying out a planned process.
• dispersion | en | The fraction of atoms of a material located at the surface of a particle.

[schumannj]

@dalito @nmoust : Any feedback here for the suggested new terms?

[dalito]

Sorry for the silence.

I would like to define "sample" as here https://nfdi4cat.github.io/pid4cat-model/ResourceCategory/ - You could either remove it from your PR or we do it before merging. We'll add the definition from pid4cat this week in another PR.

For mechanism: I think the preferred label should better not just be mechanism but chemical reaction mechanism (matching its definition). In the definition, I suggest to reword ...including a characterization as complete... to ...including a description as complete... to avoid puzzling readers by the word "characterization". The reason why we want to give the concept a more specific preferred label is that other concepts for mechanical, electrical etc. mechanisms could also find its way to voc4cat in the future.

@nmoust - can you also have a look?

[schumannj]

Thanks for the quick reply @dalito, I have removed the sample concept and have made the requested changes.

[nmoust]

@schumannj and @dalito I have no further comments. I think that the additions look good! Thanks for contributing!