Just looked at the Treaty:
Article 10:
Interest arising in U.S. and paid to resident of China may be taxed in China.
However ,such interest may also be taxed in the U.S. which it arises and
according to the law of the U.S., but if the receipient is the beneficial
owner of the interest, the tax so charged shall not exceed 10 percent of the
gross amount of the interest.
Basically you can elect not to pay tax on the interest in the U.S. but pay
them to the China's government (mostly we do not)