Research intensity for 118 elements and topics, ~10M papers. Free element scores; x402 pay-per-call.
Free
One server, in research. Research intensity for 118 elements and topics, ~10M papers. Free element scores; x402 pay-per-call.
Research
Research intensity for 118 elements and topics, ~10M papers. Free element scores; x402 pay-per-call.
The rest either hold an API key issued by the publisher or ask for nothing.
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