Abstract: The present disclosure provides a garden blower, including a housing and a duct assembly, the duct assembly includes an outer duct, a motor fan blade assembly and a guide cone; the outer duct and the rear casing are arranged in such a way that there is an annular interval therebetween, and a plurality of first anti-vibration components are arranged between the outer duct and the holding casing; the first anti-vibration components are close to the motor fan blade assembly, and form a first anti-vibration plane perpendicular to the motor axis of the motor fan blade assembly. This technical solution can suppress the transmission of vibration generated by the rotation of the motor fan blade assembly to other components, especially the holding casing, and effectively avoids the mutual influence between the vibration of the motor fan blade assembly and the disturbance of the rear casing caused by the airflow.

Abstract: The present disclosure relates to the field of drug synthesis, and discloses a method for the preparation of trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone as an intermediate of halofuginone. In the preparation method according to the present disclosure, for the first time, trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone as shown in Formula I is obtained from amino-substituted pentanal and a thiazolyl sulfoxide compound as raw materials by Mislow-Evans rearrangement reaction and subsequent Lewis acid catalysis. The method for the preparation of trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone as an intermediate of halofuginone according to the present disclosure has high yields and stable qualities, provides a new reference route for the synthesis of trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone, avoids the reduction of pyridine, and overcomes the disadvantage of requiring the use of an expensive metal catalyst Rh/A1203.