Annual report pursuant to Section 13 and 15(d)

Income taxes (Details) - Schedule of income taxes expense (benefit)

v3.22.1
Income taxes (Details) - Schedule of income taxes expense (benefit) - USD ($)
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Current:    
U.S. federal
U.S. state and local
China
Total current income taxes expense
Deferred:    
U.S. federal (1,810,264) (2,333,680)
U.S. state and local (612,904) (790,117)
China (152,015) (132,578)
Total deferred income taxes (benefit) (2,575,183) (3,256,375)
Change in valuation allowance 2,575,183 3,256,375
Total income taxes expense