My site has 10 articles per page and each articles has facebook like, tweet and google+ buttons and also in sidebar it has facebook like and subscribe button. These social elements take more time and increase my site loading time. Please give your advice.
You can't do anything to this ... The loading time of social plugins is approximately equal to (facebook example): Your page load + Facebook call and answer time + facebook library parsing your page
So you can't do anything because you are dependant of a third party ...
The only way i know to improve the loading performance is to use the channel url like described here : http://developers.facebook.com/docs/reference/javascript/FB.init/
What you want to do is use the XFBML tags, call FB.init with xfbml: false, and then after the page has loaded, you call FB.XFBML.parse(). This will effectively defer loading of the Facebook plugins until your page is done.
Now, if you want some of these rendered, earlier, then you can pass the parent node to parse and have only these rendered.
Alternatively, place the reference to all.js at the bottom of your DOM, and make sure you use the async pattern.