(corrects Sunday case number in Xian to 90 from 95 in 2nd paragraph) BEIJING (Reuters) -Xian, a Chinese city almost two weeks into a lockdown, is demanding officials “strictly and properly” implement COVID-19 curbs, as new local cases among its 13 million residents have started to grow at a slower pace. Xian, which on Dec. 23 imposed strict curbs on travel within the city and leaving town, reported 95 domestically transmitted cases with confirmed clinical symptoms for Monday, up slightly from 90 a day earlier, official data showed on Tuesday. Monday also marked the second consecutive day for w…