Shares of China Web portal Sina (SINA) dropped more than 14% Friday afternoon on expected weakness in advertising in the current quarter, despite the company beating analyst views in Q3. Sina late Thursday said Q3 sales were $147.7 million, up 17.6% and edging analyst views for $146 million. The Shanghai-based company's per-share profit, minus items, was 17 cents, a 35% drop from a year ago. But that was a lesser drop than expected. Wall Street