http://www.scopus.com/home.url
1-iop
http://iopscience.iop.org/search
2- http://www-jmg.ch.cam.ac.uk/data/c2k/cj/
3-http://www.springerlink.com/content
4-http://portal.acs.org/portal/acs/corg/content
5-http://www.sciencedirect.com/
6-
http://journals.cambridge.org/action/login;jsessionid=70BE49C02A030990AE368B51F07A0232.tomcat1
7-taylor francis
http://www.tandfonline.com/action/doSearch
8- http://www.jstor.org/action/doBasicResults
9-RSC: http://pubs.rsc.org/en
10.bentham
11.inderscience
12-wiley: http://onlinelibrary.wiley.com/browse/publications?type=journal
13, http://online.sagepub.com/search
14. http://ieeexplore.ieee.org/Xplore/home.jsp
15 AIP
http://jap.aip.org/resource/1/japiau/v97/i1/p013520_s1?isAuthorized=no