Cost-effective Φ-OTDR with laser phase noise mitigation using self-mixing interferometry.

The performances and cost of the phase-sensitive optical time-domain reflectometry (Φ-OTDR) systems are heavily influenced by the lasers used. Traditionally, Φ-OTDR systems rely on highly coherent ultra-narrow linewidth lasers (NLL). This paper proposes a Φ-OTDR system that utilizes self-mixing interferometry to mitigate the impact of laser phase noise and a triple-frequency scheme to achieve fading-free detection over 40 km.

Construction of PDA-PEI/ZIF-L@PE tight ultra-filtration (TUF) membranes on porous polyethylene (PE) substrates for efficient dye/salt separation.

Tight ultra-filtration (TUF) membranes were constructed by in situ growing zinc imidazole frameworks micro-crystalline leaves (ZIF-L) in polyethylene imine (PEI) and polydopamine (PDA) deposit layers on porous polyethylene (PE) substrates. The effects of preparation conditions on the surface physical and chemical structures as well as on the dye/salt separation performance of the formed TUF membranes were systematically investigated. By inserting selective water permeation channels and increasing contacting surface areas, in situ-grown ZIF-L arrays tightly cross-linked in the coating matrix greatly increased water permeation without trading off dye/salt retention selectivity.

Ligand Substitution: An Effective Way for Tuning Structures of ZIF-7 Nanoparticles (NPs) and Improving Energy Recovery Performance of ZIF/PA TFN Membranes.

It is an important initiative to reduce the building energy consumption using energy recovering ventilation (ERV) systems. The application of ERV systems is hindered by the low CO barrier performance of commercial total heat exchange membranes (THEMs) that lead to unsatisfactory indoor air refreshing rate, and there is an urgent need for THEMs that have improved CO barrier properties and effective energy recovery efficiencies. Here, we report the formation of novel ZIF/PA TFN THEMs based on ZIF-7-X nanoparticles (NPs) with "core-shell" structures and tunable particle sizes, formed from benzimidazole (BIM) ligands and BIM substituted by -NH, -CH, -CH, and -CH functional groups.

Optical injection locking based local oscillator regeneration for continuous variable quantum key distribution.

We develop an optical injection locking (OIL) based local oscillator (LO) regeneration for continuous variable quantum key distribution (CVQKD) by sending a weak polarization multiplexed pilot carrier from the transmitter. The OIL at the receiver has superior performance in terms of minimum input power and noise level at offset frequencies to the erbium-doped fiber amplifier (EDFA)-based scheme. The weak pilot carrier is recovered both in power and phase via the OIL while incurring little excess noise to the CVQKD system.