Abstract: A reversible electromagnetic valve and an air conditioning unit are provided. The reversible electromagnetic valve includes a valve body and a valve core assembly, the valve body is provided with a valve cavity, and the valve core assembly is arranged in the valve cavity. The valve core assembly includes a piston and a connecting rod, wherein the piston is provided with a connecting hole, one end of the connecting rod penetrates through the connecting hole and is connected with the piston, and the connecting rod includes a tapered section, an outer diameter of which gradually changes along an axial direction of the connecting rod component. The tapered section extends into the connecting hole and abuts against an inner wall of the connecting hole, so that the connecting rod component is sealed and connected with the piston.

Abstract: A method for improving a bio-coupling efficiency between a protein and a nucleic acid based on an ?-helix handle includes the following steps. First, the handle carrying the non-natural amino acid (H-tag) is designed. Then, a recombinant expression plasmid encoding a fusion protein containing the H-tag and the protein to be tested is constructed. Subsequently, the fusion recombinant protein containing the non-natural amino acid in the H-tag is expressed and purified. Finally, the non-natural amino acid in the H-tag-fused protein and the coupling group on the nucleic acid substrate are efficiently connected by click chemistry. Thea-helix handle is used to provide a controllable reaction condition on the protein surface for the non-natural amino acid, avoiding the complex structure, charge and polar nanoenvironment around the surface of the protein to be tested.

Abstract: A method for improving a bio-coupling efficiency between a protein and a nucleic acid based on an ?-helix handle includes the following steps. First, the handle carrying the non-natural amino acid (H-tag) is designed. Then, a recombinant expression plasmid encoding a fusion protein containing the H-tag and the protein to be tested is constructed. Subsequently, the fusion recombinant protein containing the non-natural amino acid in the H-tag is expressed and purified. Finally, the non-natural amino acid in the H-tag-fused protein and the coupling group on the nucleic acid substrate are efficiently connected by click chemistry. Thea-helix handle is used to provide a controllable reaction condition on the protein surface for the non-natural amino acid, avoiding the complex structure, charge and polar nanoenvironment around the surface of the protein to be tested.