Russian companies that do business with China have encountered more headwinds in recent days as Chinese banks raised the yuan-ruble exchange rate to capitalize on their neighbor's weakened currency. While the yuan currently buys 12.07 rubles at the Russian central bank's exchange rate, Chinese banks are selling the currency at 13 rubles per yuan, charging a premium over the Russian central bank rate of 12.07 rubles, the Moscow Times reported on Thursday. -snip- Chinese banks are not the first to profit from the ruble's plight. Mongolia and Turkey have for some time converted rubles into yuan several percentage points above...