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This study experimentally investigates a Regenerative Organic Rankine Cycle (RORC) system that operated under varied cryogenic conditions using liquid nitrogen (LN2) as the heat sink. A three-fluid heat exchanger (TFHE) is applied to this system instead of a condenser and regenerator to realize the RORC system. The condensing pressure changes between 0.08 MPa and 0.6 MPa, and applying the R290 as the working fluid. The condensing pressure effect on system performances, including electrical power output, cold thermal efficiency, and exergetic efficiency, are investigated under different LN2 flow rates. The comparisons between basic ORC (BORC) and RORC under the same working conditions are conducted. The results demonstrate that as the condensing pressure remains constant, the higher LN2 flow rate is beneficial to the overall performance of the RORC system. The maximum cold thermal efficiency and power generation obtained in the RORC system are 13.35% and 738.81 W, which are obtained at the LN2 flow rate of 120 kg/h and the condensing pressure of 0.25 MPa. Additionally, the RORC shows improved performance with an exergetic efficiency of 10.68%. The results would be a technological guide for the construction and improvement of the system with cold energy recovery. [ABSTRACT FROM AUTHOR]

We prepared oriented Co3+ doped M-type hexaferrites Sr0.5Ba0.5Fe12 - XCoXO19 (x = 0 - 1) with tunable anisotropy field. The magnetic properties of Sr0.5Ba0.5Fe12 - XCoXO19 with different Co3+ content were investigated. Results show that the particles of powder samples with different Co3+ content are aligned and have a similar hexagonal shape. The saturation magnetization increases firstly and then decrease with the increase in Co3+ content. The coercive field decrease sharply with little Co3+ content and then stand at a low level. Calculated magnetic anisotropy field show that substitution of Co3+ for Fe3+ can adjust the anisotropy filed from 21kOe to 15kOe. Furthermore, we also observed the sample changing from uniaxial anisotropy to plane anisotropy. [ABSTRACT FROM AUTHOR]

We propose a non-volatile 2 × 2 photonic switch based on multimode interference in an Sb 2 Se 3 -loaded waveguide. The different modal symmetries of the TE 0 and TE 1 modes supported in the multimode region change their propagation constants distinctly upon the Sb 2 Se 3 phase transition. Through careful optical design and FDTD optimization of the multimode waveguide dimensions, efficient switching is achieved despite the modest index contrast of Sb 2 Se 3 relative to Ge 2 Sb 2 Te 5 . The fabricated optical switch demonstrates favorable characteristics, including low insertion loss of ∼1 dB, a compact length of ∼27 µm, and small cross talk below -15 dB across a 35 nm bandwidth. Such non-volatile and broadband components will be critical for future high-density programmable photonic-integrated circuits for optical communications and signal processing.