Translating a scientific paper from American to British

Switch your spellchecker in MSWord to 'English (United Kingdom)' and it will catch all but the words that can be spelled correctly either way in English - there are a few 'ise' / 'ize' ending words like that. There really aren't that many words that are different if you're translating a scientific paper.

Most of the differences in technical writing are spellings. Wikipedia has an article with plenty of examples. Common ones are endings: -re instead of -er, -our instead of -or and -ise instead of -ize (though the latter is accepted by some authorities in British English. There are plenty of others. Whole words include sulphur and aluminium in some contexts - in others the spellings chosen by IUPAC (chemistry) are used whatever flavour of English is used. -ae- and -oe- are much more common in British English, a simple -e- is used in American (many words in a medical context, for example)

The other differences tend to be:

• more idiomatic and therefore less suitable for technical writing than alternative phrasing.
• widely understood, to the point that whether they're Americanisms or not is a matter for debate.
• variable between style guides anyway.

A few specific cases are worth mentioning (addressed from the point of view of academic British English):

• gotten isn't a word.
• spelt is the past tense of spell and not just a form of wheat (spelled is also acceptable).
• British English is more likely to double a final consonant when adding a suffix.
• we fly in aeroplanes not airplanes.