Abstract: The present application relates to a method for prepare a Cangrelor tetrasodium salt, comprising: using N-[2-(methylthio)ethyl]-2-[(3,3,3-trifluoropropyl)sulfonyl]adenosine as a raw material to undergo two steps of reaction to obtain a reaction solution containing the Cangrelor tetrasodium salt; separating and purifying once by C18 silica gel column chromatography so as to obtain a Cangrelor tetrasodium salt pure product. The present application has the advantages of short synthesis route, mild reaction conditions, sufficient reaction, simple operation, high product yield, high purity, and environmental friendliness, and is suitable for large-scale preparation.

Abstract: This application discloses example radio frequency identification systems and example methods for constructing a relay network, a reader, and a repeater. One example radio frequency identification system includes a reader, a repeater, and a target tag. The reader can be configured to send a first signal to the repeater. The repeater can be configured to send an excitation signal to the target tag based on the first signal. The target tag can be configured to send a target backscatter signal based on excitation of the excitation signal, where the target backscatter signal carries electronic product code information. The reader can be further configured to receive the target backscatter signal and obtain the electronic product code information in the target backscatter signal.

Abstract: The present application relates to a method for prepare a Cangrelor tetrasodium salt, comprising: using N-[2-(methylthio)ethyl]-2-[(3,3,3-trifluoropropyl)sulfonyl]adenosine as a raw material to undergo two steps of reaction to obtain a reaction solution containing the Cangrelor tetrasodium salt; separating and purifying once by C18 silica gel column chromatography so as to obtain a Cangrelor tetrasodium salt pure product. The present application has the advantages of short synthesis route, mild reaction conditions, sufficient reaction, simple operation, high product yield, high purity, and environmental friendliness, and is suitable for large-scale preparation.

Abstract: This application discloses example radio frequency identification systems and example methods for constructing a relay network, a reader, and a repeater. One example radio frequency identification system includes a reader, a repeater, and a target tag. The reader can be configured to send a first signal to the repeater. The repeater can be configured to send an excitation signal to the target tag based on the first signal. The target tag can be configured to send a target backscatter signal based on excitation of the excitation signal, where the target backscatter signal carries electronic product code information. The reader can be further configured to receive the target backscatter signal and obtain the electronic product code information in the target backscatter signal.