curl --request POST \
  --url https://rpc.quai.network/cyprus1/ \
  --header 'Content-Type: application/json' \
  --data '{
  "jsonrpc": "2.0",
  "method": "miner_setMinerPreference",
  "params": [
    0.66
  ],
  "id": 1
}'

{
  "jsonrpc": "2.0",
  "result": "true",
  "id": 1
}