water filtration (IMAGE) Penn State Caption Penn State researchers will fabricate membranes with different surface pattern geometries and sizes to use in membrane capacitive deionization. The full membrane is seen at left, and at right, a portion of the membrane is seen under an electron microscope. The tiny wells allow sodium and chloride ions be filtered out of unclean water. Credit Arges Lab/Penn State Usage Restrictions No restrictions. License Public Domain 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.