Abstract: An intelligent integrated anti-collision system and method for a pier, including: a radar sensing device disposed at the joint between the pier and a girder, image collection devices disposed around the pier, control system, hydraulic system and execution device, where the radar sensing and image collection devices transmit collected signals to the control system, which uses the hydraulic system to control the action of the execution device; the execution device is disposed at a middle part of the pier and includes a plurality of sections of steel-reinforced rubber concrete girder connected end to end through pulleys, the hydraulic system can drive the pulleys to rotate to enable the sections to be located on the same horizontal line, and an energy dissipation apparatus is disposed at the tail end of the last section to realize energy dissipation of the energy generated by impact when an object impacts the energy dissipation apparatus.

Abstract: An intelligent integrated anti-collision system and method for a pier, including: a radar sensing device disposed at the joint between the pier and a girder, image collection devices disposed around the pier, control system, hydraulic system and execution device, where the radar sensing and image collection devices transmit collected signals to the control system, which uses the hydraulic system to control the action of the execution device; the execution device is disposed at a middle part of the pier and includes a plurality of sections of steel-reinforced rubber concrete girder connected end to end through pulleys, the hydraulic system can drive the pulleys to rotate to enable the sections to be located on the same horizontal line, and an energy dissipation apparatus is disposed at the tail end of the last section to realize energy dissipation of the energy generated by impact when an object impacts the energy dissipation apparatus.

Abstract: Provided is a method for preparing 2,5-dimethylphenylacetic acid, wherein p-xylene is mixed with paraformaldehyde and concentrated hydrochloric acid in a solvent of ion liquid to obtain 2,5-dimethyl benzyl chloride by the chloromethylation reaction. Then, 2,5-dimethyl benzyl chloride is introduced into a reactor with an acid binding agent and a solvent, the carbonylation and hydrolysis reaction is conducted in the presence of a catalyst to obtain 2,5-dimethylphenylacetic acid. The present process has new route, less synthesis steps, simple operation, lower cost, increased yield, and is friendly to the environment. Therefore, the method is suitable for industrial production.

Abstract: Provided is a method for preparing 2,5-dimethylphenylacetic acid, wherein p-xylene is mixed with paraformaldehyde and concentrated hydrochloric acid in a solvent of ion liquid to obtain 2,5-dimethyl benzyl chloride by the chloromethylation reaction. Then, 2,5-dimethyl benzyl chloride is introduced into a reactor with an acid binding agent and a solvent, the carbonylation and hydrolysis reaction is conducted in the presence of a catalyst to obtain 2,5-dimethylphenylacetic acid. The present process has new route, less synthesis steps, simple operation, lower cost, increased yield, and is friendly to the environment. Therefore, the method is suitable for industrial production.