Can these day be affected, instance closed attractions and disruptive transportation (train, plane)?

Michele, it's ok to travel in Xian and Shanghai. However, travel restrictions are taken in Beijing from August 22 to September 3. Some attraction like Tiananmen Area and Forbidden City are closed. The restaurants and hotels in Wangfujing Area are not open too. If possible, you might reschedule your itinerary and visit Beijing after September 3.