Whether the public patent can be used by others?

Definitely not. The reason for the disclosure of patented technology is that the patent applicant exchanges the disclosure of the technology for a period of technical protection. If it is disclosed but not authorized in the end, you can use it as you like, but if it is authorized, do you want to Use requires the consent of the patentee.

Legal basis:

Article 42 of the "Patent Law of the People's Republic of China" states that the term of invention patent rights is twenty years, and the term of utility model patent rights is The term of design patent rights is ten years, and the term of design patent rights is fifteen years, both calculated from the date of application. If the invention patent right is granted after four years from the date of application for the invention patent and three years from the date of request for substantive examination, the patent administration department of the State Council shall, at the request of the patentee, resolve the unreasonable delay in the authorization process of the invention patent. Compensation is granted for the duration of the patent right, except for unreasonable delays caused by the applicant.