Is there an easy way or existing tool to generate a historical chart with the occurrence of one or more user-specified keyword(s) (combinations) in academic publications, based on the words in the title and/or abstract of a paper?
There is a almost-what-I-was-looking-for tool called Google Scholar Trend Miner, but it seems to be not working anymore, as it reports after hitting Go: "It seems that Google found out that we are a bot and started offering its CAPTCHA. Please, wait some hours and try again"
An easy to use and free tool for anyone without academic licences is the Scholar Plotr:
Like the Google Scholar Trend Miner mentioned in the question it only queries Google Scholar and therefore shows academic research only.