ABSTRACT
Topological photonic crystals with robust pseudo-spin and valley edge states have shown promising and wide applications in topological waveguides, lasers, and antennas. However, the limited bandwidth and intrinsic coupling properties of a single pseudo-spin or valley edge state have imposed restrictions on their multifunctional applications in integrated photonic circuits. Here, we propose a topological photonic crystal that can support pseudo-spin and valley edge states simultaneously in a single waveguiding channel, which effectively broadens the bandwidth and enables a multipath routing solution for terahertz information processing and broadcasting. We show that distorted Kekulé lattices can open two types of bandgaps with different topological properties simultaneously by molding the inter- and intra-unit cell coupling of the tight-binding model. The distinct topological origins of the edge states provide versatile signal routing paths toward free space radiation or on-chip self-localized edge modes by virtue of their intrinsic coupling properties. Such a powerful platform could function as an integrated photonic chip with capabilities of broadband on-chip signal processing and distributions that will especially benefit terahertz wireless communications.
ABSTRACT
The mechanism of radical generation in HRP-NADH-O2/H2O2 systems and state-change of horseradish peroxidase (HRP) was investigated by using ESR and UV measurements, and the novel enzyme-coenzymatic systems were performed to degrade chlorobenzene as a non-phenolic persistent organic pollutants. The UV results showed that compound III was produced from HRP oxidized by hydrogen peroxide with the catalysis of NADH, which would generate hydroxyl radical. The ESR results demonstrated the production of *OH and O2-. in enzyme-coenzymatic system in the presence of O2 or H2O2 with DMPO and POBN as spin-trappers, respectively. In HRP-NADH-H2O2 system, compound III was the main state of HRP in the initial 10 min, and then converted to HRP with generating hydroxyl radical; and after the addition of oxygen, the production of hydroxyl radical was promoted rapidly, as 4 times as that of the system in absence of oxygen. The addition of SOD(Zn-Cu) decreased the production of hydroxyl radical significantly, resulting from that SOD eliminated O2 reduction to O2-. by NADH and then inhibited *OH formation. The results showed that NADH could improve by about 20% enzyme activity of HRP for phenol removal. The removal of chlorobenzene with HRP-NADH-H2O2 and HRP-NADH-H2O2-O2 systems reached 24.6% and 48.2%, respectively, which was much higher than that with traditional enzymatic system (1.42%), showing a promising prospect in proposal
