IOPscience is available for testing at ELTE until 30 April 2017. The university's IP ranges are required to access the database.
The publisher of the Institute of Physics provides scientific journals in subject like astrophysics, geophysics, nanotechnology, nuclear fusion etc. During the trial access, the publishers journals are available in full-text.
Direct access to the journals: http://iopscience.iop.org/journalList