Nanocrystal Superlattices (IMAGE) University of Pennsylvania Caption Electron microscopes show the preparation of BNSL membranes on the left, with higher magnification shown on the right. Credit University of Pennsylvania Usage Restrictions None License Licensed 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.