ScienceDirect uses DOIs (digital object identifiers) for its permalinks.
Be sure to right click and copy the entire DOI. When you copy it, it looks like this:
http://dx.doi.org/10.1016/j.fcr.2006.11.007
You will need to add the proxy URL to the DOI:
http://libproxy.txstate.edu/login?url=http://dx.doi.org/10.1016/j.fcr.2006.11.007