The DOAJ aims to be comprehensive and cover all open access scientific and scholarly journals that use a quality control system to guarantee the content. Probably the most well-known open access journal database.
Google Scholar searches across many scholarly disciplines and sources: articles, theses, books, abstracts and court opinions, academic publishers, professional societies, online repositories, and universities with non scholarly results filtered out.
Not all of the materials found in Google Scholar are open or even free for full-text. Many of the results will provide citations or abstracts only.
Resources available in full-text should have a link to the PDF or the HTML format. You may also be able to locate a full-text version by linking to the subscription resources of the Wilkens Library, from the 
section:
PubMed Central is a free archive of biomedical and life sciences journal literature at the U.S. National Institutes of Health's National Library of Medicine. All of the articles are available in full-text. While some journals available in PubMed Central are government publications and therefore in the public domain, most materials are still under copyright restrictions. See the PMC Copyright Notice for more information.
Digital Commons Network | Free full-text scholarly articles The Digital Commons Network brings together scholarship from hundreds of universities and colleges, providing open access to peer-reviewed journal articles, book chapters, dissertations, working papers, conference proceedings, and other original scholarly work. This constantly growing body of publications is curated by university librarians and their supporting institutions, and represents thousands of disciplines and subject areas.