Synthesis of the X–Por–COF (X = NN, CC, or C/C). (IMAGE) Science China Press Caption Synthesis of the X–Por–COF (X = NN, CC, or C/C). Credit ©Science China Press Usage Restrictions Use with credit. License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.