Search

Structured photons are a crucial resource in both classical and quantum technologies, particularly in spin–orbit hybrid photons, enabling various practical applications ranging from ultra-sensitive metrology techniques to quantum-enhanced information processing tasks. However, the two-photon interference of spin–orbit hybrid photons, which combines polarization modes and complex transverse spatial structures across the beam profile, remains unexplored. Here, we present an experimental observation of Hong–Ou–Mandel (HOM) interference of spin–orbit hybrid photons. The tunable q-plates that work as spin–orbit coupler devices are used to prepare various forms of spin–orbit hybrid entangled photons. By harnessing the match degree in the temporal domain, the coalescence and anti-coalescence effects resulting from the symmetric and anti-symmetric properties of the incident quantum states are observed. Moreover, we demonstrated the feasibility of quantum-enhanced photon polarization gears through HOM interference and theoretically analyze the noise-resilient advantages based on coherent HOM measurements. These results provide an alternative route toward quantum experiments with structured photons that allows for controlling their quantum interference in a compact, stable, and efficient way. [ABSTRACT FROM AUTHOR]

In this paper, novel synergetic PtNP@Co3O4 hollow nanopolyhedrals with peroxidase-like activities are designed and prepared, which can be used as electrochemical and colorimetric signal labels for the enzyme-free dual-channel homogeneous sensing of prostate-specific antigen. When prostate-specific antigens are present, the aptamer-modified PtNP@Co3O4 hollow nanopolyhedrals and magnetic beads form sandwich structures, which have excellent peroxidase-like activities, because of the synergetic effect of PtNP@Co3O4 hollow nanopolyhedrals. The sandwich structures can be separated from the mixture by the magnetic effect of the magnetic beads and catalyze the redox reactions between H2O2 and TMB, generating quantitative electrochemical and colorimetric responses in homogeneous solution simultaneously. Under the optimized conditions, the linear range of both electrochemical (0.01 to 10 ng/ml) and colorimetric (0.01–15 ng/ml) channels can satisfy the demand of prostate-specific antigen detection in clinic (4 ng/ml), and the electrochemical and colorimetric channels have a low detection limit of 0.0079 ng/ml and 0.01 ng/ml respectively without using natural enzymes. The strategy by using synergetic PtNP@Co3O4 hollow nanopolyhedrals as signal probes provides a promising scheme for developing simple, rapid, reliable, and ultrasensitive dual-channel homogeneous biosensors, which has a great potential as a powerful tool in prostate cancer diagnosis. [ABSTRACT FROM AUTHOR]

To develop a method for direct transesterification of wet yeast using immobilized lipase, the oleaginous yeast Saitozyma podzolica Zwy-2-3 and the lipase producing Burkholderia pyrrolica WZ10-3 were used as materials for production of biodiesel. Fe 3 O 4 @SiO 2 -CHO prepared by modifying Fe 3 O 4 with TEOS, APTES and glutaraldehyde. The biocatalysts covalently cross-linked with WZ10-3 lipase by Fe 3 O 4 @SiO 2 -CHO were characterized by FTIR, XRD and TEM. When the enzyme dosage, glutaraldehyde concentration, temperature and time were 30.22 mL, 2.0%, 40 °C and 4 h, the immobilized lipase activity and immobilization rate reached 10038.0 U/g and 96.9%, respectively. The optimum temperatures for immobilized and free lipase were 60 °C and 40 °C. The immobilized enzyme still had 80% enzymatic activity after 48 d storage at 4 °C. The optimized conditions for the direct conversion of immobilized lipase to esterified wet yeast (one-step) were: enzyme dosage 2.5 g, reaction temperature 35 °C; water content 15%; and molar ratio of n-hexane to methanol 3: 1. The transesterification rates of one-step method for oil and biomass were 98.12% and 56.11%, respectively. In contrast, the two-step method was only 88.75% and 51.21%. The immobilized enzyme had 90% enzyme activity after 10 times of reuse. • Fe 3 O 4 nanoparticles stabilized by different organic ligands were prepared. • Microbial lipase was immobilized on magnetic nanoparticles by covalent cross-linking. • Direct transesterification of wet oleaginous yeast for biodiesel production. • After 10 times reuse, immobilized lipase yielded >90% enzyme activity. [ABSTRACT FROM AUTHOR]