Abstract: The present application belongs to the field of architecture, and specifically provides a multi-story modular house and its connection assembly; the connection assembly includes a connector, a first connection module for connecting with the first box, and a second connection module for connecting with the second box, and the connector has a connection part, a shear resistance part and a calibration part connected in sequence. The connection part is used to connect with the first connection module. The second connection module is equipped with a calibration hole and a grouting chamber. The shear resistance part is a tooth-like structure, and the tooth-like structure is used to connect with the irrigation The grouting materials in the grouting chamber are meshed; the first box and the second box of the multi-story modular house are connected by the above-mentioned connection assembly.

Abstract: The present disclosure belongs to the technical field of water body treatment, and particularly relates to a method for enhancing biological denitrification based on the addition of exogenous ?-cyclodextrin. Preferably, Paracoccus denitrificans and ?-cyclodextrin are added for biological denitrification enhancement. In the present disclosure, the ?-cyclodextrin is exogenously added to a denitrifying medium to construct a denitrification system, so that the denitrification rate of microorganisms may be increased and the production of harmful denitrification intermediate products is reduced.