The occurrence and transmission of chirality is af ascinating characteristic of nature.H owever,t he intermolecular transmission efficiency of circularly polarized luminescence (CPL) remains challenging due to poor throughspace energy transfer.W er eport au nique CPL transmission from inducing the achiral acceptor to emit CPL within as pecific liquid crystal (LC)-based intermolecular system through ac ircularly polarized fluorescence resonance energy transfer (C-FRET), wherein the luminescent cholesteric LC is employed as the chirality donor,a nd rationally designed achiral long-wavelength aggregation-induced emission (AIE) fluorophore acts as the well-assembled acceptor.Incontrast to photon-release-and-absorption, the chirality transmission channel of C-FRET is highly dependent upon the energy resonance in the highly intrinsic chiral assembly of cholesteric LC,a sv erified by deliberately separating the achiral acceptor from the chiral donor to keep it far beyond the resonance distance.T his C-FRET mode provides ad enovos trategy concept for high-level information processing for applications such as high-density data storage,c ombinatorial logic calculation, and multilevel data encryption and decryption.

Development of circularly polarized luminescent (CPL) materials with strong emission and high dissymmetry factor of luminescence (g lum) is highly desirable. A series of CPL-active aggregation-induced emission luminogens (AIEgens) have been successfully constructed by incorporating AIEgen dicyanodistyrylbenzene (DCS) into chiral molecule cholesterol. Benefiting from its typical AIE characteristic, DCS allows emission efficiency up to 73.7% in a condensed state. Furthermore, cholesterol units ensure forming chiral liquid crystal in syntax, and increasing the g lum value of CPL from 7 × 10–4 for the amorphous state to 1.1 × 10–1 for the liquid crystal state. This approach paves a general avenue for addressing the major defect well: high g lum always suffers from suppression of emission efficiency.

A luminescent liquid crystal molecule (TPEMes) with efficient solid-state emission is rationally constructed via the chemical conjugation of blue-emitting tetraphenylethene cores and luminescent mesogenic tolane moieties, which are both featured with aggregation-induced emission properties. As for this fluorophore, aggregation-induced energy transfer from the emissive tolane mesogens to the lighting-up tetraphenylethene units endows the molecule pure blue emission in the suspension and bulk state. Combining differential scanning calorimetry, polarized optical microscope, and one-dimensional X-ray diffraction (1D XRD) experiments, the compound TPEMes is deduced to adapt thermodynamically more stable layered crystalline phase and can be “frozen” into a monotropic smectic mesophase due to kinetic reasons. As a result of more dense packing of TPEMes in the crystalline phase indicated by 1D XRD, the luminescence of TPEMes in crystalline phase blue-shifted by 17 nm relative to the metastable mesophase.

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A moisture detection of single rice grains using a slim and small open-ended coaxial probe is presented. The coaxial probe is suitable for the nondestructive measurement of moisture values in the rice grains ranging from from 9.5% to 26%. Empirical polynomial models are developed to predict the gravimetric moisture content of rice based on measured reflection coefficients using a vector network analyzer. The relationship between the reflection coefficient and relative permittivity were also created using a regression method and expressed in a polynomial model, whose model coefficients were obtained by fitting the data from Finite Element-based simulation. Besides, the designed single rice grain sample holder and experimental set-up were shown. The measurement of single rice grains in this study is more precise compared to the measurement in conventional bulk rice grains, as the random air gap present in the bulk rice grains is excluded.