JSFiddle - React, Tailwind, and code Playground

HTML

<div id="list">
    <div class="entry-thumb">
        <img src="http://www.wareko.jp/wordpress/wp-content/uploads/2015/10/101815_0109_1-150x150.png" />
    </div>
</div>
<div class="test"></div>

JavaScript

(function ($) {
    $(function () {
		$("#list .entry-thumb img").each(function(){
        	var imgSrc = $(this).attr("src"),
            	reSrc = imgSrc.replace("-150x150", "");
            $(".test").append("<img />");
            $(".test img").attr("src",reSrc);          
        });
    });
})(jQuery);